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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:
 def detect_mbr(self, filename, offset, fs_id):
 """Used by rawdisk.session.Session to match mbr partitions against filesystem plugins. Args: filename: device or file that it will read in order to detect the filesystem fs_id: filesystem id to match (ex. 0x07) offset: offset for the filesystem that is being matched Returns: Volume object supplied by matched plugin. If there is no match, None is returned """

        self.logger.debug('Detecting MBR partition type')

        if fs_id not in self.__mbr_plugins:
            return None
        else:
            plugins = self.__mbr_plugins.get(fs_id)
            for plugin in plugins:
                if plugin.detect(filename, offset):
                    return plugin.get_volume_object()
        return None