How to use the snakeviz.main.app function in snakeviz

asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())

    # Go ahead and import the tornado app and start it; we do an inline import
    # here to avoid the extra overhead when just running the cli for --help and
    # the like

    from .main import app
    import tornado.ioloop

    # As seen in IPython:
    # https://github.com/ipython/ipython/blob/8be7f9abd97eafb493817371d70101d28640919c/IPython/html/notebookapp.py
    # See the IPython license at:
    # https://github.com/ipython/ipython/blob/master/COPYING.rst.
    for p in random_ports(port, 10):
        try:
            app.listen(p, address=hostname)
        except socket.error as e:
            print('Port {0} in use, trying another.'.format(p))
        else:
            port = p
            break
    else:
        print('No available port found.')
        return 1

    url = "http://{0}:{1}/snakeviz/{2}".format(hostname, port, filename)
    print(('snakeviz web server started on %s:%d; enter Ctrl-C to exit' %
           (hostname, port)))
    print(url)

    if not args.server:
        try: