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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 get_logger():
 """ Instantiate a logger. """

    root = logging.getLogger()
    root.setLevel(logging.WARNING)
    ch = logging.StreamHandler(sys.stderr)
    ch.setLevel(logging.DEBUG)
    formatter = logging.Formatter('%(message)s')
    ch.setFormatter(formatter)
    root.addHandler(ch)
    return root