Random SSN. (9 digits)

    Example::

        >>> rand_ssn()
        295-50-0178

def rand_ssn():
    """Random SSN. (9 digits)

    Example::

        >>> rand_ssn()
        295-50-0178
    """
    return "%s-%s-%s" % (rand_str(3, string.digits),
                         rand_str(2, string.digits),
                         rand_str(4, string.digits))