Should I Leave My `except` Clause Bare When Checking for Images with PyAutoGUI?

Concerns Raised by Leaving 'except' Bare

In an effort to identify if an image is present on the screen, you have implemented a function that utilizes PyAutoGui. While the function performs as intended, you encounter a warning from PyCharm, prompting you to refrain from leaving 'except' clauses empty.

Potential Pitfalls of Bare 'except'

Leaving 'except' bare raises potential issues as it can trap exceptions beyond your intended scope. This includes:

• KeyboardInterrupt: When a user presses Ctrl C to interrupt the program's execution.
• Python-raised errors: Errors raised internally by Python, such as SystemExit.

Appropriate Exception Handling

For effective exception handling, consider catching only specific exceptions you expect to encounter. In this case, the expected exception is pyautogui.ImageNotFoundException as per the library's documentation. A tailored 'except' block for this specific exception type would be:

def check_image_on_screen(image):
    try:
        pyautogui.locateCenterOnScreen(image)
        return True
    except pyautogui.ImageNotFoundException:
        return False

Handling Unknown Exceptions

In situations where the specific exception is unknown, it may be prudent to catch a broader base type, such as Exception. However, it's generally recommended to allow unknown exceptions to propagate up the call stack in order for them to be handled appropriately.

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