setuptools without unexpected downloads

[Ben Finney]

"Diez B. Roggisch" <deets at nospam.web.de> writes:

> Ben Finney schrieb:
> > To clarify: I want to retain the "assert the specified
> > dependencies are satisfied" behaviour, without the "... and, if
> > not, download and install them the Setuptools Way" behaviour.
> >
> > Instead, I just want the default "dependencies not satisfied"
> > behaviour for my 'setup.py' program to be: complain the
> > dependencies aren't met, and refuse to install.
> 
> The problem here is that your favorite OS vendor/distributor not
> necessarily offers the required meta-information - so setuptools
> can't check the dependencies.

Let's assume it does. How would I modify my 'setup.py' script so that
its default behaviour, when dependencies are not met, is not "download
and install dependencies via setuptools" but instead "exit with error
message"?

-- 
 \        "With Lisp or Forth, a master programmer has unlimited power |
  `\     and expressiveness. With Python, even a regular guy can reach |
_o__)                            for the stars."  -- Raymond Hettinger |
Ben Finney