Honestly, I feel like TRY is overreaching here. There's no way that return (dst, 1) is going to cause an OSError, and re-writing with the else clause just distracts from the typical control flow.

In general, this rule might help identify cases where it's not clear which part of the code may throw. The usefulness of the TRY300 rule depends on the context: number of lines and complexity of the code under try.

In this specific case, it is quite clear that the return line won't raise en exception. On the other hand, I do not find the else clause less readable. The typical control flow is important of course, but so is clarity about what is tested under try. Additionally, the error control flow feels important too, enough to have 3 lines of comments.