@staticmethod
  def GetModuleFile(module, is_file=os.path.isfile):
    module_file = getattr(module, '__file__', None)
    if module_file is None:
      return None


    source_file = module_file[:module_file.rfind('py') + 2]

    if is_file(source_file):
      return source_file
    return module.__file__
step should be incremented when we go to the next page
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/tools/dev_appserver.py/ModuleManager.GetModuleFile--crossover with--dataset/ETHPy150Open dcramer/django-compositepks/django/contrib/formtools/tests.py/WizardTests.test_step_increments