code: def _compile_update_columns(self, values):
          
          columns = []
  
          for key, value in values.items():
              columns.append("%s = %s" % (self.wrap(key), self.parameter(value)))
  
          return ", ".join(columns)
docs: Compile the columns for the update statement
  
          :param values: The columns
          :type values: dict
  
          :return: The compiled columns
          :rtype: str