nowgiven these constraints and assumptionswe can allow for both keywords and omitted default arguments in the call with this algorithm when call is interceptedwe can make the following assumptions and deductions let be the number of passed positional argumentsobtained from the length of the *pargs tuple all positional arguments in *pargs must match the first expected arguments obtained from the function' code object this is true per python' call ordering rulesoutlined earliersince all positionals precede all keywords in call to obtain the names of arguments actually passed by positionwe can slice the list of all expected arguments up to the length of the *pargs passed positionals tuple any arguments after the first expected arguments either were passed by keyword or were defaulted by omission at the call for each argument name to be validated by the decoratora if the name is in **kargsit was passed by name--indexing **kargs gives its passed value if the name is in the first expected argumentsit was passed by position-its relative position in the expected list gives its relative position in *pargs otherwisewe can assume it was omitted in the call and defaultedand need not be checked in other wordswe can skip tests for arguments that were omitted in call by assuming that the first actually passed positional arguments in *pargs must match the first argument names in the list of all expected argumentsand that any others must either have been passed by keyword and thus be in **kargsor have been defaulted under this schemethe decorator will simply skip any argument to be checked that was omitted between the rightmost positional argument and the leftmost keyword argumentbetween keyword argumentsor after the rightmost positional in general trace through the decorator and its test script to see how this is realized in code open issues although our range-testing tool works as plannedthree caveats remain--it doesn' detect invalid callsdoesn' handle some arbitrary-argument signaturesand doesn' fully support nesting improvements may require extension or altogether different approaches here' quick rundown of the issues invalid calls firstas mentioned earliercalls to the original function that are not valid still fail in our final decorator the following both trigger exceptionsfor example decorators