The Python Apprentice

Empty blocks – the pass statement

With that said, we still have the problem of what to do with our empty except block. The solution arrives in the form of the pass keyword, which is a special statement that does precisely nothing! It's a no-op, and it's only purpose is to allow us to construct syntactically permissible blocks that are semantically empty:

def convert(s):    """Convert a string to an integer."""    x = -1    try:        x = int(s)    except (ValueError, TypeError):        pass    return x

In this case though, it would be better to simplify further by using multiple return statements, doing away with the x variable completely:

def convert(s):    """Convert a string to an integer."""    try:        return int(s)    except (ValueError, TypeError):        return -1