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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_targmax(self, value):
 """ The maximum number of targets certain types of commands can affect. """

        if not value:
            return

        for entry in value.split(','):
            command, limit = entry.split(':', 1)
            if not limit:
                continue
            self._target_limits[command] = int(limit)