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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 realise(self):
 """ Realise the future if possible If the future has not been realised yet, do so in the current thread. This will block execution until the future is realised. Otherwise, do not block but return whether the result is already available. This will not return the result nor propagate any exceptions of the future itself. :return: whether the future has been realised :rtype: bool """

        if self._mutex.acquire(False):
            # realise the future in this thread
            try:
                if self._result is not None:
                    return True
                call, args, kwargs = self._instruction
                try:
                    result = call(*args, **kwargs)
                except BaseException as err:
                    self._result = None, err
                else:
                    self._result = result, None
                return True
            finally:
                self._mutex.release()
        else:
            # indicate whether the executing thread is done
            return self._result is not None