Finally block always runs in python, avoid returning values in this block

>>> def foo():
...    try:
...        return 1
...    except:
...        return 2
...    finally:
...        return 3
... 
>>> foo()
3
>>> def foo():
...     try:
...        raise ValueError
...     except:
...        return 2
...     finally:
...        return 3
... 
>>> foo()
3

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