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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def on_isupport_maxbans(self, value):
 """ Maximum entries in ban list. Replaced by MAXLIST. """

        if 'MAXLIST' not in self._isupport:
            if not self._list_limits:
                self._list_limits = {}
            self._list_limits['b'] = int(value)