import six


def _get_col_values_count(col_values):
  """
  Helper that returns the length of the first list in among the values of col_values. If none of
  the values is a list, returns 1.
  """
  first_list = next((v for v in six.itervalues(col_values) if isinstance(v, list)), None)
  return len(first_list) if first_list is not None else 1