Understanding the Python with statement and context managers

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with doesn’t really replace try/except, but, rather, try/finally. Still, you can make a context manager do something different in exception cases from non-exception ones:

class Mgr(object):
    def __enter__(self): pass
    def __exit__(self, ext, exv, trb):
        if ext is not None: print "no not possible"
        print "OK I caught you"
        return True

with Mgr():
    name="rubicon"/2 #to raise an exception

The return True part is where the context manager decides to suppress the exception (as you do by not re-raising it in your except clause).

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