to fix this you need your pycharm to use python (version) 3.1 :
delete pycharm and python
https://www.jetbrains.com/pycharm/download/#section=windows
https://www.python.org/downloads/
on the pycharm IDE:
Press Ctrl+Alt+S to open the project Settings/Preferences and go to Project: <project name> | Python Interpreter. Click the Add Interpreter link next to the list of the available interpreters.
Select Add Local Interpreter from the list of the available interpreter types,
and choose 3.1
delete pycharm and python
https://www.jetbrains.com/pycharm/download/#section=windows
https://www.python.org/downloads/
on the pycharm IDE:
Press Ctrl+Alt+S to open the project Settings/Preferences and go to Project: <project name> | Python Interpreter. Click the Add Interpreter link next to the list of the available interpreters.
Select Add Local Interpreter from the list of the available interpreter types,
and choose 3.1