code: def later_than(after, before):
      
      if isinstance(after, six.string_types):
          after = str_to_time(after)
      elif isinstance(after, int):
          after = time.gmtime(after)
  
      if isinstance(before, six.string_types):
          before = str_to_time(before)
      elif isinstance(before, int):
          before = time.gmtime(before)
  
      if before is None:
          return True
      if after is None:
          return False
      return after >= before
docs: True if then is later or equal to that