Creates extractors to extract properties corresponding to 'col_params'.

  Args:
    col_params: List of ListSessionGroupsRequest.ColParam protobufs.
  Returns:
    A list of extractor functions. The ith element in the
    returned list extracts the column corresponding to the ith element of
    _request.col_params

def _create_extractors(col_params):
  """Creates extractors to extract properties corresponding to 'col_params'.

  Args:
    col_params: List of ListSessionGroupsRequest.ColParam protobufs.
  Returns:
    A list of extractor functions. The ith element in the
    returned list extracts the column corresponding to the ith element of
    _request.col_params
  """
  result = []
  for col_param in col_params:
    result.append(_create_extractor(col_param))
  return result