Which exception should I raise on bad/illegal argument combinations in Python?

Question

I was wondering about the best practices for indicating invalid argument combinations in Python. I\'ve come across a few situations where you have a function like so:

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Answer 1

Agree with Markus' suggestion to roll your own exception, but the text of the exception should clarify that the problem is in the argument list, not the individual argument values. I'd propose:

class BadCallError(ValueError):
    pass

Used when keyword arguments are missing that were required for the specific call, or argument values are individually valid but inconsistent with each other. ValueError would still be right when a specific argument is right type but out of range.

Shouldn't this be a standard exception in Python?

In general, I'd like Python style to be a bit sharper in distinguishing bad inputs to a function (caller's fault) from bad results within the function (my fault). So there might also be a BadArgumentError to distinguish value errors in arguments from value errors in locals.