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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 serialize_task_id(self):
 """ Create a unique identifier for the current location within the task. The format is C{b"<task_uuid>@<task_level>"}. @return: L{bytes} encoding the current location within the task. """

        return "{}@{}".format(
            self._identification[TASK_UUID_FIELD],
            self._nextTaskLevel().toString()).encode("ascii")