Python, Tkinter, and flask runtime 0xC0000005

I can't show the code. I made a gui for tkinter and a api for flask. gui start a Thread and api start as a Thread. Api got a queue, when I request to api. A value put to queue. Then gui's thread always get the queue. while got it, change the label. But now when I request the gui exit for code 0xC0000005.

One of the reasons for the exception exit is found: put blocks the queue and get blocks, and an error occurs; put USES put_nowait to avoid that.