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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 describe_guest(userid):
 """ Get the basic information of virtual machine. Input parameters: :userid: USERID of the guest, last 8 if length > 8 """

    # Check if the guest exists.
    guest_list_info = client.send_request('guest_list')
    userid_1 = (unicode(userid, "utf-8") if sys.version[0] == '2' else userid)

    if userid_1 not in guest_list_info['output']:
        raise RuntimeError("Guest %s does not exist!" % userid)


    guest_describe_info = client.send_request('guest_get_definition_info', userid)
    print("\nThe created guest %s's info are: \n%s\n" % (userid, guest_describe_info))