code: def mom_version(name='marathon-user'):
      
      if service_available_predicate(name):
          with marathon_on_marathon(name):
                  return marathon_version()
      else:
          # We can either skip the corresponding test by returning False
          # or raise an exception.
          print('WARN: {} MoM not found. Version is None'.format(name))
          return None
docs: Returns the version of marathon on marathon.