def __init__(self, name, host='127.0.0.1', port=27017):
        self.name = name
        self.host = host
        self.port = port
def test_regex_bad_input():
    cases = (
        'abc',
        '123abc',
        'abc123',
        '',
    )

    num_only = inputs.regex(r'^[0-9]+$')

    for value in cases:
        yield assert_raises, ValueError, lambda: num_only(value)