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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 main():
 """Start an interactive `MockupDB`. Use like ``python -m mockupdb``. """

    from optparse import OptionParser
    parser = OptionParser('Start mock MongoDB server')
    parser.add_option('-p', '--port', dest='port', default=27017,
                      help='port on which mock mongod listens')
    parser.add_option('-q', '--quiet',
                      action='store_false', dest='verbose', default=True,
                      help="don't print messages to stdout")

    options, cmdline_args = parser.parse_args()
    if cmdline_args:
        parser.error('Unrecognized argument(s): %s' % ' '.join(cmdline_args))

    server = interactive_server(port=options.port, verbose=options.verbose)
    try:
        server.run()
        print('Listening on port %d' % server.port)
        time.sleep(1e6)
    except KeyboardInterrupt:
        server.stop()