PyautoGUI- How to use If - Else with pyautogui.locateCenterOnScreen

[Tiel]

Essentially I want my Python script to perform this...

     x = True
     if x  == True:
         print('Congratulations, you won!')
     else:
         print('I'm sorry but you lost.')

with this...

     a, b = pyautogui.locateCenterOnScreen('~/home/file_01.png', region=(1065,250,385,700), confidence=0.9)

In other words, how can I have my script check to see if PyautoGUI has successfully located the center of ~/home/file_01.png?

See, about 95% of the time the following works correctly....

     a, b = pyautogui.locateCenterOnScreen('~/home/file_01.png', region=(1065,250,385,700), confidence=0.9)

But about 5% of the time ~/home/file_01.png does not exist. In those cases my script stops and throws off the following error message...

     TypeError: cannot unpack non-iterable NoneType object

Instead of having my script stops in cases when ~/home/file_01.png does not exist I would prefer that my script skip that instance. In other words, instead of stopping I want my script to ignore cases when ~/home/file_01.png does not exist.