def _str_dotted_getattr(obj, name):
    """Expands extends getattr to allow dots in x to indicate nested objects.

    Args:
       obj (object): an object.
       name (str): a name for a field in the object.

    Returns:
       Any: the value of named attribute.

    Raises:
       AttributeError: if the named attribute does not exist.
    """
    for part in name.split('.'):
        obj = getattr(obj, part)
    return str(obj) if obj else None