invalid syntax error when using for loop on a zip object

Question

I'm learning how to optimize for loops in python 3.7, and I keep getting an "invalid syntax error". I've already checked for missing parenthesis. Here's the code:

    best = probabilities[0]
    best = (probabilities[i] for i in range(1, len(probabilities)) if probabilities[i] > best)
    print(best)
    prob, im = (prob, im for prob, im in zip(probabilities, image_names) if prob == best)

    return (prob, im)

gives me the error

  File "path", line 27
    prob, im = (prob, im for prob, im in zip(probabilities, image_names) if prob == best)
                           ^
SyntaxError: invalid syntax

I'm not sure what went wrong, as the following code I used in another exercise uses pretty much the same syntax:

im = [im for im, prob in zip(image_names, probabilities) if prob >= threshold]
    return (im)

Edit: I've also tried

return (prob, im for prob, im in zip(probabilities, image_names) if prob == best)

and it says that the variable type is a Generator[tuple[float, str], Any, None] but I'm not sure what it means.

Any help would be very appreciated

Answer 1

Tuples need to be explicitly wrapped in () when being produced by a comprehension/generator expression:

((prob, im) for prob, im in zip(probabilities, image_names) if prob == best)