def dist(a, b):
    return sum((i-j)**2 for i, j in zip(a, b))
def check_url_error_message(value):
    try:
        inputs.url(value)
        assert False, u"inputs.url({0}) should raise an exception".format(value)
    except ValueError as e:
        assert_equal(six.text_type(e),
                     (u"{0} is not a valid URL. Did you mean: http://{0}".format(value)))