[Distutils] [proposal] module dependency specification and overriding for packages

[Ronny Pfannschmidt]

Hi,

while trying to vendor packages that depend on six, i noticed a 
problematic implication

it is impossible to do this without patching those modules, as such 
adding a fragile maintenance burden.

in order to elevate that i propose creating a mechanism that allows to 
physically or virtually map sets of interdependent libraries (that are 
prepared for it into a sub-package of the package vendor-ing it

this would elevate a few issues
a) removing the need to patch
b) making de-vendor-ing of exact versions trivial (just unpacked wheels 
and adding it to the sub-packages __path__)
c) easing updates, as the vendor-ing turns into a process of fetching 
the wheels and unpacking them into the package folder

i do have some implementation ideas, but i would like to hear the 
opinions of others before proposing an exact implementation

-- Ronny