Why Does My Recursive Python Function Return None?

Recursive Function Returns None in Python: Addressing the Issue

In certain scenarios when employing recursive functions in Python, it's possible to encounter a situation where the function returns None instead of the desired value. This issue commonly arises when the function is intended to return a specific path, but the actual result retrieved is None.

One potential cause for this problem is the omission of a return statement after the recursive call. To resolve this, the function should explicitly return the result of the recursive call. Modifying the code to include a return statement will ensure that the function returns the necessary path:

else:
    return get_path(directory[filename], rqfile, path)

Additionally, it's advisable to consistently include a return statement at the end of the function, regardless of the outcome of the recursive call. This practice ensures that the function will always return a value, avoiding the possibility of returning None erroneously:

for filename in dictionary.keys():
    path = prefix+[filename]
    if not isinstance(dictionary[filename], dict):
        if rqfile in str(os.path.join(*path)):
            return str(os.path.join(*path))

    return get_path(directory[filename], rqfile, path)

By implementing these suggested adjustments, the recursive function will return the intended path rather than None, resolving the issue encountered.

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