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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 control(controllee: Union['cirq.Gate', op_tree.OP_TREE], control_qubits: Sequence['cirq.Qid'] = None, default: Any = RaiseTypeErrorIfNotProvided) -> Any: """Returns a Controlled version of the given value, if defined. Controllees define how to be controlled by defining a method controlled_by(self, control_qubits). Note that the method may return NotImplemented to indicate a particular controlling can't be done. Args: controllee: The gate, operation or iterable of operations to control. control_qubits: A list of Qids that would control this controllee. default: Determines the fallback behavior when `controllee` doesn't have a controlling defined. If `default` is not set and the fallback occurs, a TypeError is raised instead. Returns: If `controllee` has a controlled_by method that returns something besides NotImplemented, that result is returned. For an OP_TREE, transformation is applied at the leaf. Otherwise, if a default value was specified, the default value is returned. Raises: TypeError: `controllee` doesn't have a controlled_by method (or that method returned NotImplemented) and no `default` was specified. """

    if control_qubits is None:
        control_qubits = []
    controller = getattr(controllee, 'controlled_by', None)
    result = NotImplemented if controller is None else controller(
                                                           *control_qubits)
    if result is not NotImplemented:
        return result

    if isinstance(controllee, collections.Iterable):
        return op_tree.transform_op_tree(
            controllee,
            op_transformation=lambda op: control(op, control_qubits))

    if default is not RaiseTypeErrorIfNotProvided:
        return default

    if controller is None:
        raise TypeError("object of type '{}' has no controlled_by "
                        "method.".format(type(controllee)))
    raise TypeError("object of type '{}' does have a controlled_by method, "
                    "but it returned NotImplemented.".format(type(controllee)))