diff --git a/gluon/sqlhtml.py b/gluon/sqlhtml.py
index 73600ef5..9f5f62d7 100644
--- a/gluon/sqlhtml.py
+++ b/gluon/sqlhtml.py
@@ -41,13 +41,15 @@ try:
     import gluon.settings as settings
     is_gae = settings.global_settings.web2py_runtime_gae
 except ImportError:
-    is_gae = False # this is an assumption (if settings missing)
+    is_gae = False  # this is an assumption (if settings missing)
 
 widget_class = re.compile('^\w*')
 
-def add_class(a,b):
+
+def add_class(a, b):
     return a+' '+b if a else b
 
+
 def represent(field, value, record):
     f = field.represent
     if not callable(f):
@@ -83,18 +85,18 @@ def show_if(cond):
     base = "%s_%s" % (cond.first.tablename, cond.first.name)
     if ((cond.op.__name__ == 'EQ' and cond.second == True) or
         (cond.op.__name__ == 'NE' and cond.second == False)):
-        return base,":checked"
+        return base, ":checked"
     if ((cond.op.__name__ == 'EQ' and cond.second == False) or
         (cond.op.__name__ == 'NE' and cond.second == True)):
-        return base,":not(:checked)"
+        return base, ":not(:checked)"
     if cond.op.__name__ == 'EQ':
-        return base,"[value='%s']" % cond.second
+        return base, "[value='%s']" % cond.second
     if cond.op.__name__ == 'NE':
-        return base,"[value!='%s']" % cond.second
+        return base, "[value!='%s']" % cond.second
     if cond.op.__name__ == 'CONTAINS':
-        return base,"[value~='%s']" % cond.second
-    if cond.op.__name__ == 'BELONGS' and isinstance(cond.second,(list,tuple)):
-        return base,','.join("[value='%s']" % (v) for v in cond.second)
+        return base, "[value~='%s']" % cond.second
+    if cond.op.__name__ == 'BELONGS' and isinstance(cond.second, (list, tuple)):
+        return base, ','.join("[value='%s']" % (v) for v in cond.second)
     raise RuntimeError("Not Implemented Error")
 
 
@@ -124,7 +126,7 @@ class FormWidget(object):
             _name=field.name,
             requires=field.requires,
         )
-        if getattr(field,'show_if',None):
+        if getattr(field, 'show_if', None):
             trigger, cond = show_if(field.show_if)
             attr['_data-show-trigger'] = trigger
             attr['_data-show-if'] = cond
@@ -191,9 +193,11 @@ class TimeWidget(StringWidget):
 class DateWidget(StringWidget):
     _class = 'date'
 
+
 class DatetimeWidget(StringWidget):
     _class = 'datetime'
 
+
 class TextWidget(FormWidget):
     _class = 'text'
 
@@ -209,6 +213,7 @@ class TextWidget(FormWidget):
         attr = cls._attributes(field, default, **attributes)
         return TEXTAREA(**attr)
 
+
 class JSONWidget(FormWidget):
     _class = 'json'
 
@@ -226,6 +231,7 @@ class JSONWidget(FormWidget):
         attr = cls._attributes(field, default, **attributes)
         return TEXTAREA(**attr)
 
+
 class BooleanWidget(FormWidget):
     _class = 'boolean'
 
@@ -294,7 +300,7 @@ class ListWidget(StringWidget):
             _class = 'string'
         requires = field.requires if isinstance(
             field.requires, (IS_NOT_EMPTY, IS_LIST_OF)) else None
-        if isinstance(value,str): value = [value]
+        if isinstance(value, str): value = [value]
         nvalue = value or ['']
         items = [LI(INPUT(_id=_id, _class=_class, _name=_name,
                           value=v, hideerror=k < len(nvalue) - 1,
@@ -335,7 +341,7 @@ class RadioWidget(OptionsWidget):
         see also: `FormWidget.widget`
         """
 
-        if isinstance(value, (list,tuple)):
+        if isinstance(value, (list, tuple)):
             value = str(value[0])
         else:
             value = str(value)
@@ -408,7 +414,7 @@ class CheckboxesWidget(OptionsWidget):
         attr = cls._attributes(field, {}, **attributes)
         attr['_class'] = add_class(attr.get('_class'), 'web2py_checkboxeswidget')
 
-        label = attr.get('label',True)
+        label = attr.get('label', True)
 
         requires = field.requires
         if not isinstance(requires, (list, tuple)):
@@ -449,7 +455,7 @@ class CheckboxesWidget(OptionsWidget):
                                        requires=attr.get('requires', None),
                                        hideerror=True, _value=k,
                                        value=r_value),
-                                 LABEL(v, _for='%s%s' % (field.name, k)) 
+                                 LABEL(v, _for='%s%s' % (field.name, k))
                                  if label else ''))
             opts.append(child(tds))
 
@@ -522,7 +528,7 @@ class UploadWidget(FormWidget):
             download_url: url for the file download (default = None)
         """
 
-        default = dict(_type='file',)
+        default = dict(_type='file', )
         attr = cls._attributes(field, default, **attributes)
 
         inp = INPUT(**attr)
@@ -555,7 +561,7 @@ class UploadWidget(FormWidget):
             else:
                 inp = DIV(inp,
                           SPAN('[',
-                               A(current.T(cls.GENERIC_DESCRIPTION),_href=url),
+                               A(current.T(cls.GENERIC_DESCRIPTION), _href=url),
                                ']', _style='white-space:nowrap'),
                           br, image)
         return inp
@@ -814,6 +820,7 @@ def formstyle_bootstrap(form, fields):
             parent.append(DIV(label, _controls, _class='control-group', _id=id))
     return parent
 
+
 def formstyle_bootstrap3(form, fields):
     """ bootstrap 3 format form layout
 
@@ -865,7 +872,7 @@ def formstyle_bootstrap3(form, fields):
 
         if _submit:
             # submit button has unwrapped label and controls, different class
-            parent.append(DIV(label, DIV(controls,_class="col-lg-4 col-lg-offset-2"), _class='form-group', _id=id))
+            parent.append(DIV(label, DIV(controls, _class="col-lg-4 col-lg-offset-2"), _class='form-group', _id=id))
             # unflag submit (possible side effect)
             _submit = False
         else:
@@ -1224,7 +1231,7 @@ class SQLFORM(FORM):
             css = 'delete'
             for f in self.table.fields:
                 on_del = self.table[f].ondelete
-                if isinstance(on_del,str) and 'cascade' in on_del.lower():
+                if isinstance(on_del, str) and 'cascade' in on_del.lower():
                     css += ' cascade_delete'
                     break
             widget = INPUT(_type='checkbox',
@@ -1286,7 +1293,7 @@ class SQLFORM(FORM):
                 for id, a, b, c in xfields:
                     newrows = formstyle(id, a, b, c)
                     self.field_parent[id] = getattr(b, 'parent', None) \
-                        if isinstance(b,XmlComponent) else None
+                        if isinstance(b, XmlComponent) else None
                     if type(newrows).__name__ != "tuple":
                         newrows = [newrows]
                     for newrow in newrows:
@@ -1295,7 +1302,7 @@ class SQLFORM(FORM):
                 table = formstyle(self, xfields)
                 for id, a, b, c in xfields:
                     self.field_parent[id] = getattr(b, 'parent', None) \
-                        if isinstance(b,XmlComponent) else None
+                        if isinstance(b, XmlComponent) else None
         else:
             raise RuntimeError('formstyle not supported')
         return table
@@ -1727,7 +1734,7 @@ class SQLFORM(FORM):
             else:
                 ftype = field.type.split(' ')[0]
             if ftype.startswith('decimal'): ftype = 'double'
-            elif ftype=='bigint': ftype = 'integer'
+            elif ftype == 'bigint': ftype = 'integer'
             elif ftype.startswith('big-'): ftype = ftype[4:]
             # end
             options = search_options.get(ftype, None)
@@ -1736,43 +1743,43 @@ class SQLFORM(FORM):
                     field.label, str) and T(field.label) or field.label
                 selectfields.append(OPTION(label, _value=str(field)))
                 operators = SELECT(*[OPTION(T(option), _value=option) for option in options])
-                _id = "%s_%s" % (value_id,name)
+                _id = "%s_%s" % (value_id, name)
                 if field.type == 'boolean':
-                    value_input = SQLFORM.widgets.boolean.widget(field,field.default,_id=_id)
+                    value_input = SQLFORM.widgets.boolean.widget(field, field.default, _id=_id)
                 elif field.type == 'double':
-                    value_input = SQLFORM.widgets.double.widget(field,field.default,_id=_id)
+                    value_input = SQLFORM.widgets.double.widget(field, field.default, _id=_id)
                 elif field.type == 'time':
-                    value_input = SQLFORM.widgets.time.widget(field,field.default,_id=_id)
+                    value_input = SQLFORM.widgets.time.widget(field, field.default, _id=_id)
                 elif field.type == 'date':
                     iso_format = {'_data-w2p_date_format' : '%Y-%m-%d'}
-                    value_input = SQLFORM.widgets.date.widget(field,field.default,_id=_id, **iso_format)
+                    value_input = SQLFORM.widgets.date.widget(field, field.default, _id=_id, **iso_format)
                 elif field.type == 'datetime':
                     iso_format = iso_format = {'_data-w2p_datetime_format' : '%Y-%m-%d %H:%M:%S'}
-                    value_input = SQLFORM.widgets.datetime.widget(field,field.default,_id=_id, **iso_format)
+                    value_input = SQLFORM.widgets.datetime.widget(field, field.default, _id=_id, **iso_format)
                 elif (field.type.startswith('reference ') or
                       field.type.startswith('list:reference ')) and \
-                      hasattr(field.requires,'options'):
+                      hasattr(field.requires, 'options'):
                     value_input = SELECT(
                         *[OPTION(v, _value=k)
-                          for k,v in field.requires.options()],
+                          for k, v in field.requires.options()],
                          **dict(_id=_id))
                 elif field.type == 'integer' or \
                         field.type.startswith('reference ') or \
                         field.type.startswith('list:integer') or \
                         field.type.startswith('list:reference '):
-                    value_input = SQLFORM.widgets.integer.widget(field,field.default,_id=_id)
+                    value_input = SQLFORM.widgets.integer.widget(field, field.default, _id=_id)
                 else:
                     value_input = INPUT(
                         _type='text', _id=_id, _class=field.type)
 
                 new_button = INPUT(
-                    _type="button", _value=T('New Search'), _class="btn btn-default", _title = T('Start building a new search'),
-                    _onclick="%s_build_query('new','%s')" % (prefix,field))
+                    _type="button", _value=T('New Search'), _class="btn btn-default", _title=T('Start building a new search'),
+                    _onclick="%s_build_query('new','%s')" % (prefix, field))
                 and_button = INPUT(
-                    _type="button", _value=T('+ And'), _class="btn btn-default", _title = T('Add this to the search as an AND term'),
+                    _type="button", _value=T('+ And'), _class="btn btn-default", _title=T('Add this to the search as an AND term'),
                     _onclick="%s_build_query('and','%s')" % (prefix, field))
                 or_button = INPUT(
-                    _type="button", _value=T('+ Or'), _class="btn btn-default",_title = T('Add this to the search as an OR term'),
+                    _type="button", _value=T('+ Or'), _class="btn btn-default", _title=T('Add this to the search as an OR term'),
                     _onclick="%s_build_query('or','%s')" % (prefix, field))
                 close_button = INPUT(
                     _type="button", _value=T('Close'), _class="btn btn-default",
@@ -1786,8 +1793,8 @@ class SQLFORM(FORM):
                         _style='display:inline'))
 
         criteria.insert(0, SELECT(
-            _id=fields_id,
-                _onchange="jQuery('.w2p_query_row').hide();jQuery('#%s_'+jQuery('#%s').val().replace('.','-')).show();" % (field_id,fields_id),
+                _id=fields_id,
+                _onchange="jQuery('.w2p_query_row').hide();jQuery('#%s_'+jQuery('#%s').val().replace('.','-')).show();" % (field_id, fields_id),
                 _style='float:left',
                 *selectfields))
 
@@ -1805,14 +1812,13 @@ class SQLFORM(FORM):
           if(aggregator=='new') k.val(s); else k.val((v?(v+' '+ aggregator +' '):'')+s);
         }
         """ % dict(
-                prefix=prefix,fields_id=fields_id,keywords_id=keywords_id,
-                field_id=field_id,value_id=value_id
-                )
+                   prefix=prefix, fields_id=fields_id, keywords_id=keywords_id,
+                   field_id=field_id, value_id=value_id
+                   )
         )
         return CAT(
             DIV(_id=panel_id, _style="display:none;", *criteria), fadd)
 
-
     @staticmethod
     def grid(query,
              fields=None,
@@ -1972,7 +1978,7 @@ class SQLFORM(FORM):
         if user_signature:
             if not (
                 '/'.join(str(a) for a in args) == '/'.join(request.args) or
-                URL.verify(request,user_signature=user_signature,
+                URL.verify(request, user_signature=user_signature,
                            hash_vars=False) or
                 (request.args(len(args))=='view' and not logged)):
                 session.flash = T('not authorized')
@@ -2001,7 +2007,7 @@ class SQLFORM(FORM):
                          _class=ui.get('buttontext'),
                          cid=request.cid)
 
-        dbset = db(query,ignore_common_filters=ignore_common_filters)
+        dbset = db(query, ignore_common_filters=ignore_common_filters)
         tablenames = db._adapter.tables(dbset.query)
         if left is not None:
             if not isinstance(left, (list, tuple)):
@@ -2012,21 +2018,21 @@ class SQLFORM(FORM):
         if fields:
             #add missing tablename to virtual fields
             for table in tables:
-                for k,f in table.iteritems():
-                    if isinstance(f,Field.Virtual):
+                for k, f in table.iteritems():
+                    if isinstance(f, Field.Virtual):
                         f.tablename = table._tablename
             columns = [f for f in fields if f.tablename in tablenames]
         else:
             fields = []
             columns = []
-            filter1 = lambda f:isinstance(f,Field)
-            filter2 = lambda f:isinstance(f,Field) and f.readable
+            filter1 = lambda f:isinstance(f, Field)
+            filter2 = lambda f:isinstance(f, Field) and f.readable
             for table in tables:
                 fields += filter(filter1, table)
                 columns += filter(filter2, table)
-                for k,f in table.iteritems():
+                for k, f in table.iteritems():
                     if not k.startswith('_'):
-                        if isinstance(f,Field.Virtual) and f.readable:
+                        if isinstance(f, Field.Virtual) and f.readable:
                             f.tablename = table._tablename
                             fields.append(f)
                             columns.append(f)
@@ -2039,7 +2045,7 @@ class SQLFORM(FORM):
                 field_id = groupby.first #take the first groupby field
         table = field_id.table
         tablename = table._tablename
-        if not any(str(f)==str(field_id) for f in fields):
+        if not any(str(f) == str(field_id) for f in fields):
             fields = [f for f in fields]+[field_id]
         if upload == '<default>':
             upload = lambda filename: url(args=['download', filename])
@@ -2069,8 +2075,8 @@ class SQLFORM(FORM):
         def linsert(lst, i, x):
             """Internal use only: inserts x list into lst at i pos::
 
-                a = [1,2]
-                linsert(a, 1, [0,3])
+                a = [1, 2]
+                linsert(a, 1, [0, 3])
                 a = [1, 0, 3, 2]
             """
             lst[i:i] = x
@@ -2174,14 +2180,14 @@ class SQLFORM(FORM):
                 redirect(referrer, client_side=client_side_delete)
 
         exportManager = dict(
-            csv_with_hidden_cols=(ExporterCSV_hidden, 'CSV (hidden cols)',T('Comma-separated export including columns not shown; fields from other tables are exported as raw values for faster export')),
-            csv=(ExporterCSV, 'CSV',T('Comma-separated export of visible columns. Fields from other tables are exported as they appear on-screen but this may be slow for many rows')),
-            xml=(ExporterXML, 'XML',T('XML export of columns shown')),
-            html=(ExporterHTML, 'HTML',T('HTML export of visible columns')),
-            json=(ExporterJSON, 'JSON',T('JSON export of visible columns')),
+            csv_with_hidden_cols=(ExporterCSV_hidden, 'CSV (hidden cols)', T('Comma-separated export including columns not shown; fields from other tables are exported as raw values for faster export')),
+            csv=(ExporterCSV, 'CSV', T('Comma-separated export of visible columns. Fields from other tables are exported as they appear on-screen but this may be slow for many rows')),
+            xml=(ExporterXML, 'XML', T('XML export of columns shown')),
+            html=(ExporterHTML, 'HTML', T('HTML export of visible columns')),
+            json=(ExporterJSON, 'JSON', T('JSON export of visible columns')),
             tsv_with_hidden_cols=
-                (ExporterTSV, 'TSV (Spreadsheets, hidden cols)',T('Spreadsheet-optimised export of tab-separated content including hidden columns. May be slow')),
-            tsv=(ExporterTSV, 'TSV (Spreadsheets)',T('Spreadsheet-optimised export of tab-separated content, visible columns only. May be slow.')))
+                (ExporterTSV, 'TSV (Spreadsheets, hidden cols)', T('Spreadsheet-optimised export of tab-separated content including hidden columns. May be slow')),
+            tsv=(ExporterTSV, 'TSV (Spreadsheets)', T('Spreadsheet-optimised export of tab-separated content, visible columns only. May be slow.')))
         if not exportclasses is None:
             """
             remember: allow to set exportclasses=dict(csv=False, csv_with_hidden_cols=False) to disable the csv format
@@ -2202,20 +2208,20 @@ class SQLFORM(FORM):
                         orderby = (order[:1] == '~' and ~sort_field) or sort_field
 
             expcolumns = [str(f) for f in columns]
-            selectable_columns = [str(f) for f in columns if not isinstance(f,Field.Virtual)]
+            selectable_columns = [str(f) for f in columns if not isinstance(f, Field.Virtual)]
             if export_type.endswith('with_hidden_cols'):
                 #expcolumns = [] start with the visible columns, which includes visible virtual fields
-                selectable_columns=[]  #like expcolumns but excluding virtual
+                selectable_columns = []  #like expcolumns but excluding virtual
                 for table in tables:
                     for field in table:
                         if field.readable and field.tablename in tablenames:
                             if not str(field) in expcolumns:
                                 expcolumns.append(str(field))
-                            if not(isinstance(field,Field.Virtual)):
+                            if not(isinstance(field, Field.Virtual)):
                                 selectable_columns.append(str(field))
                     #look for virtual fields not displayed (and virtual method fields to be added here?)
-                    for (field_name,field) in table.iteritems():
-                        if isinstance(field,Field.Virtual) and not str(field) in expcolumns:
+                    for (field_name, field) in table.iteritems():
+                        if isinstance(field, Field.Virtual) and not str(field) in expcolumns:
                              expcolumns.append(str(field))
 
             if export_type in exportManager and exportManager[export_type]:
@@ -2223,7 +2229,7 @@ class SQLFORM(FORM):
                     try:
                         #the query should be constructed using searchable fields but not virtual fields
                         sfields = reduce(lambda a, b: a + b,
-                            [[f for f in t if f.readable and not isinstance(f,Field.Virtual)] for t in tables])
+                            [[f for f in t if f.readable and not isinstance(f, Field.Virtual)] for t in tables])
                         dbset = dbset(SQLFORM.build_query(
                             sfields, request.vars.get('keywords', '')))
                         rows = dbset.select(left=left, orderby=orderby,
@@ -2233,11 +2239,11 @@ class SQLFORM(FORM):
                         rows = []
                 else:
                     rows = dbset.select(left=left, orderby=orderby,
-                                    cacheable=True, *selectable_columns)
+                                        cacheable=True, *selectable_columns)
 
                 value = exportManager[export_type]
                 clazz = value[0] if hasattr(value, '__getitem__') else value
-                rows.colnames = expcolumns # expcolumns is all cols to be exported including virtual fields
+                rows.colnames = expcolumns  # expcolumns is all cols to be exported including virtual fields
                 oExp = clazz(rows)
                 filename = '.'.join(('rows', oExp.file_ext))
                 response.headers['Content-Type'] = oExp.content_type
@@ -2373,17 +2379,17 @@ class SQLFORM(FORM):
                                    not all([isinstance(link, dict) for link in links])))
         if include_buttons_column:
             if buttons_placement in ['right', 'both']:
-                headcols.append(TH(_class=ui.get('default','')))
+                headcols.append(TH(_class=ui.get('default', '')))
                 right_cols += 1
             if buttons_placement in ['left', 'both']:
-                headcols.insert(0, TH(_class=ui.get('default','')))
+                headcols.insert(0, TH(_class=ui.get('default', '')))
                 left_cols += 1
 
         head = TR(*headcols, **dict(_class=ui.get('header')))
 
         cursor = True
         #figure out what page we are one to setup the limitby
-        if paginate and dbset._db._adapter.dbengine=='google:datastore':
+        if paginate and dbset._db._adapter.dbengine == 'google:datastore':
             cursor = request.vars.cursor or True
             limitby = (0, paginate)
             try: page = int(request.vars.page or 1)-1
@@ -2391,22 +2397,22 @@ class SQLFORM(FORM):
         elif paginate and paginate<nrows:
             try: page = int(request.vars.page or 1)-1
             except ValueError: page = 0
-            limitby = (paginate*page,paginate*(page+1))
+            limitby = (paginate*page, paginate*(page+1))
         else:
             limitby = None
         try:
             table_fields = [field for field in fields
-                            if (field.tablename in tablenames and not(isinstance(field,Field.Virtual)))]
-            if dbset._db._adapter.dbengine=='google:datastore':
-                rows = dbset.select(left=left,orderby=orderby,
-                                    groupby=groupby,limitby=limitby,
+                            if (field.tablename in tablenames and not(isinstance(field, Field.Virtual)))]
+            if dbset._db._adapter.dbengine == 'google:datastore':
+                rows = dbset.select(left=left, orderby=orderby,
+                                    groupby=groupby, limitby=limitby,
                                     reusecursor=cursor,
-                                    cacheable=True,*table_fields)
+                                    cacheable=True, *table_fields)
                 next_cursor = dbset._db.get('_lastcursor', None)
             else:
-                rows = dbset.select(left=left,orderby=orderby,
-                                    groupby=groupby,limitby=limitby,
-                                    cacheable=True,*table_fields)
+                rows = dbset.select(left=left, orderby=orderby,
+                                    groupby=groupby, limitby=limitby,
+                                    cacheable=True, *table_fields)
         except SyntaxError:
             rows = None
             next_cursor = None
@@ -2414,31 +2420,31 @@ class SQLFORM(FORM):
         except Exception, e:
             rows = None
             next_cursor = None
-            error = T("Query Not Supported: %s")%e
+            error = T("Query Not Supported: %s") % e
 
         message = error
         if not message and nrows:
-            if dbset._db._adapter.dbengine=='google:datastore' and nrows>=1000:
+            if dbset._db._adapter.dbengine == 'google:datastore' and nrows >= 1000:
                 message = T('at least %(nrows)s records found') % dict(nrows=nrows)
             else:
                 message = T('%(nrows)s records found') % dict(nrows=nrows)
-        console.append(DIV(message or T('None'),_class='web2py_counter'))
+        console.append(DIV(message or T('None'), _class='web2py_counter'))
 
         paginator = UL()
-        if paginate and dbset._db._adapter.dbengine=='google:datastore':
+        if paginate and dbset._db._adapter.dbengine == 'google:datastore':
             #this means we may have a large table with an unknown number of rows.
             try:
                 page = int(request.vars.page or 1)-1
             except ValueError:
                 page = 0
-            paginator.append(LI('page %s'%(page+1)))
+            paginator.append(LI('page %s' % (page+1)))
             if next_cursor:
                 d = dict(page=page+2, cursor=next_cursor)
-                if order: d['order']=order
-                if request.vars.keywords: d['keywords']=request.vars.keywords
+                if order: d['order'] = order
+                if request.vars.keywords: d['keywords'] = request.vars.keywords
                 paginator.append(LI(
-                    A('next',_href=url(vars=d),cid=request.cid)))
-        elif paginate and paginate<nrows:
+                    A('next', _href=url(vars=d), cid=request.cid)))
+        elif paginate and paginate < nrows:
             npages, reminder = divmod(nrows, paginate)
             if reminder:
                 npages += 1
@@ -2475,13 +2481,13 @@ class SQLFORM(FORM):
 
         if rows:
             cols = [COL(_id=str(c).replace('.', '-'),
-                        data={'column': left_cols + i + 1}) 
-                    for i,c in enumerate(columns)]
+                        data={'column': left_cols + i + 1})
+                    for i, c in enumerate(columns)]
             cols = [COL(data={'column': i + 1}) for i in range(left_cols)] + \
                    cols + \
                    [COL(data={'column': left_cols + len(cols) + i + 1})
                     for i in range(right_cols)]
-            htmltable = TABLE(COLGROUP(*cols),THEAD(head))
+            htmltable = TABLE(COLGROUP(*cols), THEAD(head))
             tbody = TBODY()
             numrec = 0
             for row in rows:
@@ -2490,7 +2496,7 @@ class SQLFORM(FORM):
                 if selectable:
                     trcols.append(
                         INPUT(_type="checkbox", _name="records", _value=id,
-                                    value=request.vars.records))
+                              value=request.vars.records))
                 for field in columns:
                     if not field.readable:
                         continue
@@ -2525,7 +2531,7 @@ class SQLFORM(FORM):
                     elif not isinstance(value, DIV):
                         value = field.formatter(value)
                     trcols.append(TD(value))
-                row_buttons = TD(_class='row_buttons',_nowrap=True)
+                row_buttons = TD(_class='row_buttons', _nowrap=True)
                 if links and links_in_grid:
                     toadd = []
                     for link in links:
@@ -2629,7 +2635,7 @@ class SQLFORM(FORM):
                     order=request.vars.order or '',
                     _export_type=k,
                     keywords=request.vars.keywords or ''))
-                export_links.append(A(T(label), _href=link,_title=title,_class='btn btn-default'))
+                export_links.append(A(T(label), _href=link, _title=title, _class='btn btn-default'))
             export_menu = \
                 DIV(T('Export:'), _class="w2p_export_menu", *export_links)
         else:
@@ -2670,15 +2676,15 @@ class SQLFORM(FORM):
         Example:
             given you defined a model as::
 
-                db.define_table('person',Field('name'),format='%(name)s')
+                db.define_table('person', Field('name'), format='%(name)s')
                 db.define_table('dog',
-                    Field('name'),Field('owner',db.person),format='%(name)s')
-                db.define_table('comment',Field('body'),Field('dog',db.dog))
+                    Field('name'), Field('owner', db.person), format='%(name)s')
+                db.define_table('comment', Field('body'), Field('dog', db.dog))
                 if db(db.person).isempty():
                     from gluon.contrib.populate import populate
-                    populate(db.person,300)
-                    populate(db.dog,300)
-                    populate(db.comment,1000)
+                    populate(db.person, 300)
+                    populate(db.dog, 300)
+                    populate(db.comment, 1000)
 
             in a controller, you can do::
 
@@ -2708,10 +2714,11 @@ class SQLFORM(FORM):
             constraints = {}
         field = None
         name = None
-        def format(table,row):
+
+        def format(table, row):
             if not row:
                 return T('Unknown')
-            elif isinstance(table._format,str):
+            elif isinstance(table._format, str):
                 return table._format % row
             elif callable(table._format):
                 return table._format(row)
@@ -2743,7 +2750,7 @@ class SQLFORM(FORM):
                             raise HTTP(400)
                     previous_tablename, previous_fieldname, previous_id = \
                         tablename, fieldname, id
-                    name = format(db[referee],record)
+                    name = format(db[referee], record)
                     breadcrumbs.append(
                         LI(A(T(db[referee]._plural),
                              cid=request.cid,
@@ -2790,19 +2797,19 @@ class SQLFORM(FORM):
         if linked_tables is None:
             linked_tables = db.tables()
         if isinstance(linked_tables, dict):
-            linked_tables = linked_tables.get(table._tablename,[])
+            linked_tables = linked_tables.get(table._tablename, [])
         if linked_tables:
             for item in linked_tables:
                 tb = None
-                if isinstance(item,Table) and item._tablename in check:
+                if isinstance(item, Table) and item._tablename in check:
                     tablename = item._tablename
                     linked_fieldnames = check[tablename]
                     tb = item
-                elif isinstance(item,str) and item in check:
+                elif isinstance(item, str) and item in check:
                     tablename = item
                     linked_fieldnames = check[item]
                     tb = db[item]
-                elif isinstance(item,Field) and item.name in check.get(item._tablename,[]):
+                elif isinstance(item, Field) and item.name in check.get(item._tablename, []):
                     tablename = item._tablename
                     linked_fieldnames = [item.name]
                     tb = item.table
@@ -2827,7 +2834,7 @@ class SQLFORM(FORM):
             header = table._plural
             next = grid.create_form or grid.update_form or grid.view_form
             breadcrumbs.append(LI(
-                    A(T(header), cid=request.cid,_href=url()),
+                    A(T(header), cid=request.cid, _href=url()),
                     SPAN(divider, _class='divider') if next else '',
                     _class='active w2p_grid_breadcrumb_elem'))
             if grid.create_form:
@@ -2842,7 +2849,7 @@ class SQLFORM(FORM):
                                   grid.view_form.record))
             if next:
                 breadcrumbs.append(LI(
-                            A(T(header), cid=request.cid,_href=url()),
+                            A(T(header), cid=request.cid, _href=url()),
                             _class='active w2p_grid_breadcrumb_elem'))
             grid.insert(
                 0, DIV(UL(*breadcrumbs, **{'_class': breadcrumbs_class}),
@@ -2880,10 +2887,10 @@ class SQLTABLE(TABLE):
     Extracolumns example
     ::
 
-        [{'label':A('Extra',_href='#'),
+        [{'label':A('Extra', _href='#'),
         'class': '', #class name of the header
         'width':'', #width in pixels or %
-        'content':lambda row, rc: A('Edit',_href='edit/%s'%row.id),
+        'content':lambda row, rc: A('Edit', _href='edit/%s'%row.id),
         'selected': False #agregate class selected to this column}]
 
 
@@ -2921,7 +2928,7 @@ class SQLTABLE(TABLE):
         if headers == 'fieldname:capitalize':
             headers = {}
             for c in columns:
-                (t,f) = REGEX_TABLE_DOT_FIELD.match(c).groups()
+                (t, f) = REGEX_TABLE_DOT_FIELD.match(c).groups()
                 headers[t + '.' + f] = f.replace('_', ' ').title()
         elif headers == 'labels':
             headers = {}
@@ -2930,7 +2937,7 @@ class SQLTABLE(TABLE):
                 field = sqlrows.db[t][f]
                 headers[c] = field.label
         if colgroup:
-            cols = [COL(_id=c.replace('.', '-'), data={'column': i + 1}) 
+            cols = [COL(_id=c.replace('.', '-'), data={'column': i + 1})
                     for i, c in enumerate(columns)]
             if extracolumns:
                 cols += [COL(data={'column': len(cols) + i + 1})
@@ -3167,13 +3174,14 @@ class ExportClass(object):
     def export(self):
         raise NotImplementedError
 
+
 class ExporterTSV(ExportClass):
     label = 'TSV'
     file_ext = "csv"
     content_type = "text/tab-separated-values"
 
     def __init__(self, rows):
-        ExportClass.__init__(self,rows)
+        ExportClass.__init__(self, rows)
 
     def export(self):
         out = cStringIO.StringIO()
@@ -3203,6 +3211,7 @@ class ExporterTSV(ExportClass):
             out.truncate(0)
         return str(final.getvalue())
 
+
 class ExporterCSV(ExportClass):
     #CSV, represent == True
     label = 'CSV'
@@ -3215,11 +3224,12 @@ class ExporterCSV(ExportClass):
     def export(self):  #export CSV with rows.represent
         if self.rows:
             s = cStringIO.StringIO()
-            self.rows.export_to_csv_file(s,represent=True)
+            self.rows.export_to_csv_file(s, represent=True)
             return s.getvalue()
         else:
             return None
 
+
 class ExporterCSV_hidden(ExportClass):
     #pure csv, no represent.
     label = 'CSV'
@@ -3227,7 +3237,7 @@ class ExporterCSV_hidden(ExportClass):
     content_type = "text/csv"
 
     def __init__(self, rows):
-        ExportClass.__init__(self,rows)
+        ExportClass.__init__(self, rows)
 
     def export(self):
         if self.rows:
@@ -3235,6 +3245,7 @@ class ExporterCSV_hidden(ExportClass):
         else:
             return ''
 
+
 class ExporterHTML(ExportClass):
     label = 'HTML'
     file_ext = "html"
@@ -3247,6 +3258,7 @@ class ExporterHTML(ExportClass):
         xml = self.rows.xml() if self.rows else ''
         return '<html>\n<head>\n<meta http-equiv="content-type" content="text/html; charset=UTF-8" />\n</head>\n<body>\n%s\n</body>\n</html>' % (xml or '')
 
+
 class ExporterXML(ExportClass):
     label = 'XML'
     file_ext = "xml"
@@ -3261,6 +3273,7 @@ class ExporterXML(ExportClass):
         else:
             return '<rows></rows>'
 
+
 class ExporterJSON(ExportClass):
     label = 'JSON'
     file_ext = "json"