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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 run(hostname=None, port=None, path=None, loop=None):
 """ The arguments are not all optional. Either a path or hostname+port should be specified; you have to specify one. """

    if path:
        log.debug("Starting Opentrons server application on {}".format(
            path))
        hostname, port = None, None
    else:
        log.debug("Starting Opentrons server application on {}:{}".format(
            hostname, port))
        path = None

    web.run_app(init(loop), host=hostname, port=port, path=path)