docs: def GetValuesForAttribute(self, attribute, only_one=False):
      """Returns a list of values from this attribute."""
      if not only_one and self.age_policy == NEWEST_TIME:
        raise ValueError("Attempting to read all attribute versions for an "
                         "object opened for NEWEST_TIME. This is probably "
                         "not what you want.")
  
      if attribute is None:
        return []
  
      elif isinstance(attribute, string_types):
        attribute = Attribute.GetAttributeByName(attribute)
  
      return attribute.GetValues(self)