code: def check_exp(self, claim='exp', current_time=None):
          
          if current_time is None:
              current_time = self.current_time
  
          try:
              claim_value = self.payload[claim]
          except KeyError:
              raise TokenError(format_lazy(_("Token has no '{}' claim"), claim))
  
          claim_time = datetime_from_epoch(claim_value)
          if claim_time <= current_time:
              raise TokenError(format_lazy(_("Token '{}' claim has expired"), claim))
docs: Checks whether a timestamp value in the given claim has passed (since
          the given datetime value in `current_time`).  Raises a TokenError with
          a user-facing error message if so.