In the core chapter of the book I found this: In the above example, both request.args[i] and request.args(i) can be used to retrieve the i-th element of the request.args, but while the former raises an exception if the list does not have such an index, the latter returns None in this case.
I would use request.args(0) and test for None if it is legal for the arg to not to be there on some requests. Conversely, if arg 0 is always supposed to be part of the request then request.args[0] would generate an exception and a ticket indicating a failure condition when it is missing.
