[Python-ideas] make __closure__ writable

[Nathan Rice]

As one of the resident crackpot/idealists I don't know that my +1
means much, but I have a decent amount of code where I jump through a
lot of hoops to emulate writable __closure__, including copying a
function using FunctionType(), then replace one instance of a function
with another multiple places in a function graph; I also do a lot of
lambda wrapping and unwrapping for the same purpose.  This is
primarily relevant relative to symbolic computation graphs, such as
dataflow structures, computer algebra systems, etc.