ModuleNotFoundError: No module named '_tkinter'

[0xZuk0]

2022-01-16T14:39:40.120585+00:00 app[web.1]: File "", line 1007, in _find_and_load
2022-01-16T14:39:40.120599+00:00 app[web.1]: File "", line 986, in _find_and_load_unlocked
2022-01-16T14:39:40.120613+00:00 app[web.1]: File "", line 680, in _load_unlocked
2022-01-16T14:39:40.120627+00:00 app[web.1]: File "", line 850, in exec_module
2022-01-16T14:39:40.120657+00:00 app[web.1]: File "", line 228, in _call_with_frames_removed
2022-01-16T14:39:40.120671+00:00 app[web.1]: from .routers import post, users, auth, vote
2022-01-16T14:39:40.120685+00:00 app[web.1]: File "/app/./app/routers/post.py", line 4, in
2022-01-16T14:39:40.120686+00:00 app[web.1]: from .. import schemas, models, oauth2
2022-01-16T14:39:40.120700+00:00 app[web.1]: from turtle import st
2022-01-16T14:39:40.120714+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.9/turtle.py", line 107, in
2022-01-16T14:39:40.120714+00:00 app[web.1]: import tkinter as TK
2022-01-16T14:39:40.120744+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.9/tkinter/init.py", line 37, in
2022-01-16T14:39:40.120744+00:00 app[web.1]: import _tkinter # If this fails your Python may not be configured for Tk
2022-01-16T14:39:40.120770+00:00 app[web.1]: ModuleNotFoundError: No module named '_tkinter'
2022-01-16T14:39:42.317479+00:00 heroku[web.1]: Error R10 (Boot timeout) -> Web process failed to bind to $PORT within 60 seconds of launch
2022-01-16T14:39:42.480091+00:00 heroku[web.1]: Process exited with status 137

I'm getting this error when i'm trying to deploy application in heroku.
I'v tried adding tkinter into requirements.txt and redeploy but it doesn't work.