assert app._is_running

i try to use this sequence of code but when i i execute session.prompt at the second time i have this error : assert app._is_running

is there a better sequence of coding ?
our_history = FileHistory('.example-history-file')
session = PromptSession(history=our_history)
batch = GBatch()
args = batch.parser.parse_args()
batch.init(args)
print ("Welcome ", batch.player)
args.func(args)
guru = True

while True:
    with patch_stdout():
        cmd = session.prompt(" >> ")
    if cmd:
        args = batch.parser.parse_args(cmd.split())
        args.cmde = cmd
        args.func(args)
        if batch.bye:
            break

here the trace
AssertionError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/Users/bruno/gsprompt/venv/lib/python3.7/site-packages/prompt_toolkit/eventloop/base.py", line 129, in call_exception_handler
self._exception_handler(context)
File "/Users/bruno/gsprompt/venv/lib/python3.7/site-packages/prompt_toolkit/application/application.py", line 702, in handle_exception
run_coroutine_in_terminal(print_exception)
File "/Users/bruno/gsprompt/venv/lib/python3.7/site-packages/prompt_toolkit/application/run_in_terminal.py", line 62, in run_coroutine_in_terminal
assert app._is_running
AssertionError

Reproduce the supplied PromptSession sequence, including the second session.prompt call and patch_stdout context. Start by reading prompt_toolkit/eventloop/base.py, prompt_toolkit/application/application.py, and prompt_toolkit/application/run_in_terminal.py around the reported assertion. Done means the sequence no longer raises AssertionError, or the supported calling sequence and limitation are documented with a regression test.