def is_empty(value):
    """
    if value is None returns True.

    if value is empty iterable (for example, empty str or emptry list),
    returns true
    otherwise false

    Note: For not iterable values, behaivour is undefined.

    :param value:
    :return:
    """
    if value is None:
        return True
    if value:
        ret = False
    else:
        ret = True
    return ret
