It's necessary to specify exact version of async_tkinter_loop

[insolor]

There were some changes in the API of async-tkinter-loop.

Since version 0.2.0 there are no more separate async_command and async_event_handler functions in the async-tkinter-loop package. Now, there is only one async_handler function for both use cases.

You need either specify the exact version async-tkinter-loop==0.1.0 in the README.md or in requrements.txt, or use async_handler instead of async_command in your code.

Sorry for the inconvenience.