How to use the sysrepo.Subscribe function in sysrepo

module_name = "ietf-interfaces"
    if len(sys.argv) > 1:
        module_name = sys.argv[1]
    else:
        print ("\nYou can pass the module name to be subscribed as the first argument")

    print ("Application will watch for changes in " +  module_name + "\n")

    # connect to sysrepo
    conn = sr.Connection(sr.SR_CONN_DEFAULT)

    # start session
    sess = sr.Session(conn)

    # subscribe for changes in running config */
    subscribe = sr.Subscribe(sess)

    subscribe.module_change_subscribe(module_name, module_change_cb, None)

    print ("\n\n ========== READING RUNNING CONFIG: ==========\n")
    try:
        print_current_config(sess, module_name);
    except Exception as e:
        print (e)

    sr.global_loop()
    
    subscribe.unsubscribe()

    sess.session_stop()

    conn=None

# Here it is useful because `Conenction`, `Session` and `Subscribe` could throw an exception.
try:
    module_name = "ietf-interfaces"
    if len(sys.argv) > 1:
        module_name = sys.argv[1]
    else:
        print ("\nYou can pass the module name to be subscribed as the first argument")

    # connect to sysrepo
    conn = sr.Connection(sr.SR_CONN_DEFAULT)

    # start session
    sess = sr.Session(conn)

    # subscribe for changes in running config */
    subscribe = sr.Subscribe(sess)

    subscribe.module_change_subscribe(module_name, module_change_cb, None, None, 0, sr.SR_SUBSCR_DONE_ONLY)

    print ("\n\n ========== READING RUNNING CONFIG: ==========\n")
    try:
        print_current_config(sess, module_name)
    except Exception as e:
        print (e)

    sr.global_loop()
    
    subscribe.unsubscribe()

    sess.session_stop()

    conn=None

# Here it is useful because `Conenction`, `Session` and `Subscribe` could throw an exception.
try:
    module_name = "ietf-interfaces"
    if len(sys.argv) > 1:
        module_name = sys.argv[1]
    else:
        print ("\nYou can pass the module name to be subscribed as the first argument")

    # connect to sysrepo
    conn = sr.Connection(sr.SR_CONN_DEFAULT)

    # start session 
    sess = sr.Session(conn)

    # subscribe for changes in running config */
    subscribe = sr.Subscribe(sess)

    print ("\nApplication will provide data of " + module_name + " module\n")

    #try:
    subscribe.oper_get_items_subscribe(module_name, "/ietf-interfaces:interfaces-state", oper_get_items_cb1)
    #except Exception as e:
    #    print (e)

    sr.global_loop()

    subscribe.unsubscribe()

    sess.session_stop()

    conn=None