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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 batch_remove(self, removals: Iterable[Tuple[int, ops.Operation]]) -> None: """Removes several operations from a circuit. Args: removals: A sequence of (moment_index, operation) tuples indicating operations to delete from the moments that are present. All listed operations must actually be present or the edit will fail (without making any changes to the circuit). ValueError: One of the operations to delete wasn't present to start with. IndexError: Deleted from a moment that doesn't exist. """

        copy = self.copy()
        for i, op in removals:
            if op not in copy._moments[i].operations:
                raise ValueError(
                    "Can't remove {} @ {} because it doesn't exist.".format(
                        op, i))
            copy._moments[i] = ops.Moment(
                old_op
                for old_op in copy._moments[i].operations
                if op != old_op)
        self._device.validate_circuit(copy)
        self._moments = copy._moments