def is_list_entity(row_value):
    """All list entities have the following structure:

         {"key": [{<data>}]}

    so this function tests specifically this.

    Args:
        row_value: Object to test
    """
    if not isinstance(row_value, dict):
        return False
    if len(row_value) != 1:
        return False
    nested_value = next(iter(row_value.values()))
    return isinstance(nested_value, list)