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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 checked_run(cmd):
 """Prepare and run a subprocess cmd, checking for successful completion."""

    completed_process = run(cmd)
    if completed_process.returncode > 0:
        print("Command failed!  Hanging around in case someone needs a "
              "docker connection. (Ctrl-C to quit now)")
        time.sleep(300)
        raise RuntimeError
    return completed_process