I believe we're decided that no one needs this and that it may even be hazardous — especially when acceptingFraction(2.5, 4.5) when the entire point of the fractions module is to achieve exactness by working with integer arithmetic.

I concur with@rhettinger.

I am even think that ifFraction() is called with two arguments, both of them must be integers. But the ship is already sailed, and I am not want to argue about deprecating the current behavior (accepting Rationals).