def assertMatches(self, text, regex):
    """Corresponding re.match version of assertRegexpMatches."""
    m = re.match(regex, text)
    if not m:
      self.fail((text, regex) % 'Text %s was not matched by pattern %s.')
dataset/ETHPy150Open GoogleCloudPlatform/appengine-mapreduce/python/test/mapreduce/main_test.py/MainTest.assertMatches/swapped operands of `%`