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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 _getThread(self, given_thread_id=None, given_thread_type=None):
 """ Checks if thread ID is given, checks if default is set and returns correct values :raises ValueError: If thread ID is not given and there is no default :return: Thread ID and thread type :rtype: tuple """

        if given_thread_id is None:
            if self._default_thread_id is not None:
                return self._default_thread_id, self._default_thread_type
            else:
                raise ValueError("Thread ID is not set")
        else:
            return given_thread_id, given_thread_type