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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 _cancel_grpc(operations_stub, operation_name):
 """Cancel an operation using a gRPC client. Args: operations_stub (google.longrunning.operations_pb2.OperationsStub):
 The gRPC operations stub. operation_name (str):
 The name of the operation. """

    request_pb = operations_pb2.CancelOperationRequest(name=operation_name)
    operations_stub.CancelOperation(request_pb)