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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_chanlimit(self, value):
 """ Simultaneous channel limits for user. """

        self._channel_limits = {}

        for entry in value.split(','):
            types, limit = entry.split(':')

            # Assign limit to channel type group and add lookup entry for type.
            self._channel_limits[frozenset(types)] = int(limit)
            for prefix in types:
                self._channel_limit_groups[prefix] = frozenset(types)