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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_iter(base_dir, control_name=CONTROL_NAME):
 """ Generate the names of all control files under base_dir """

    controls = (os.path.join(p, control_name) for p, _, fs in os.walk(base_dir)
                if control_name in fs)
    return controls