About the action limitation on Webshop

[zzh068]

Hello, this is a brilliant work~
May I ask about this code in https://github.com/noahshinn024/reflexion/blob/49485efc8fa2514dd98edfb8427ed27ad06fb391/webshop_runs/webshop_trial.py#L168

            elif button == 'Next >':
                assert False # ad hoc page limitation
                assert self.sessions[session]['page_type'] == 'search'
                self.sessions[session]['page_num'] += 1
            elif button == '< Prev':
                assert self.sessions[session]['page_type'] in ['search', 'item_sub', 'item']
                if self.sessions[session]['page_type'] == 'search':
                    assert False

the original Webshop env seems implemented the [Next] and [Prev] buttion, why here set to False?
I would appreciate if you could give me answer.