I don’t think it is a Python barrel. The rib looks different and appears to be a separate piece.You have an extensively modified Colt Police Positive Special.
Some sort of adjustable rear sight has been roughly fitted to the frame. possibly a S&W sight.
The original barrel has been replaced with what appears to be a heavily modified Colt Python barrel, which has had the original markings replaced rather crudely.
The ejector rod head is missing, and the hammer spur has been cut off.
This is what it originally looked like..........
View attachment 814028
There's little value left after all the poorly done alterations, and it may not even be safe to fire.