How to check if a Widget exists?

I want to check if a button from Tkinter exists before I remove it.

To implement this, I wrote the following code:

if btn_process.winfo_exists():
    btn_process.grid_remove()

When the Button does exist, everything works fine. Although, when it doesn’t exist yet, an error message shows up in the console:

TypeError: Misc.winfo_exists() missing 1 required positional argument: ‘self’

The code is inside a function, and I also tried to declare this button as a global variable so that it exists, and put the ‘global btn_process’ at the beginning of the function, which still doesn’t work.

This error only occurs when I first check for the nonexisting button. If I create it, delete it and delete it again, there is no error.

How can I handle this error? I’m new to Python and don’t know how to interpret this error.