code: def is_tuple_end(self, extra_end_rules=None):
          
          if self.stream.current.type in ('variable_end', 'block_end', 'rparen'):
              return True
          elif extra_end_rules is not None:
              return self.stream.current.test_any(extra_end_rules)
          return False
docs: Are we at the end of a tuple?