code: def refresh(self):
          
          block = self.blockchain.rpc.get_block(self.identifier)
          if not block:
              raise BlockDoesNotExistsException
          super(Block, self).__init__(
              block, blockchain_instance=self.blockchain, use_cache=self._use_cache
          )
docs: Even though blocks never change, you freshly obtain its contents
              from an API with this method