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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 stop_all_tensorboards():
 """Terminate all TensorBoard instances."""

    for process in Process.instances:
        print("Process '%s', running %d" % (process.command[0],
                                            process.is_running()))
        if process.is_running() and process.command[0] == "tensorboard":
            process.terminate()