code: def _parse_function_return_types_from_doc(cls, doc):
          
          data = dict(name='', col_types=[], col_names=[], _type=None)
          if doc:
              return_doc = __doc__.split(':return')[-1].strip()
              data['name'] = return_doc.split(':')[0]
              if data['name'].startswith('list of'):
                  if data['name'].endswith('LIST'):
                      data['_type'] = 'list_list'
                      for row in return_doc.split('\n')[3:]:
                          index, col_type, col_name = row.split(None, 2)
                          assert (index == str(index))
                          data['col_types'].append(col_type)
                          data['col_names'].append(col_name.split()[0])
          return data
docs: This will extract the return type for list of lists so that the
          repr can display the header.
          :param doc:  str of the function doc
          :return      dict of {func.__name__:{'api_type':'type','col_name':[],
                                               'col_type':[],'repr_type':None}}