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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 compile_default_action(self, batch_size: Optional[int] = None) -> Sequence[tf.Tensor]:
        '''Returns a tuple of tensors representing the default action fluents.

        Args:
            batch_size (int): The batch size.

        Returns:
            Sequence[tf.Tensor]: A tuple of tensors.
        '''
        with self.graph.as_default():
            with tf.name_scope('default_action'):
                self._initialize_default_action_fluents()
                if batch_size is None:
                    return self.default_action_fluents
                return self._compile_batch_fluents(self.default_action_fluents, batch_size)