Appends operations onto the end of the circuit.

        Moments within the operation tree are appended intact.

        Args:
            moment_or_operation_tree: The moment or operation tree to append.
            strategy: How to pick/create the moment to put operations into.

def append(
            self,
            moment_or_operation_tree: Union[ops.Moment, ops.OP_TREE],
            strategy: InsertStrategy = InsertStrategy.EARLIEST):
        """Appends operations onto the end of the circuit.

        Moments within the operation tree are appended intact.

        Args:
            moment_or_operation_tree: The moment or operation tree to append.
            strategy: How to pick/create the moment to put operations into.
        """
        self.insert(len(self._moments), moment_or_operation_tree, strategy)