[PEAK] dumb question about easy_install

[Michael Bayer]

OK, im just not understanding how to override a site-packages egg  
install with a local (development) install, egg or otherwise.

i have the package installed as a setuptools egg in the global site- 
packages.   normally, this is what i want.  PYTHONPATH is not set.

but then, I want to be able to cd into a directory somewhere where  
theres a newer/older version of the package, and run some scripts  
against that one.

I cd into my local checkout of the same application.  say its in a  
directory "sa020" and the python files are in "./lib/sqlalchemy/".

	cd ~/sa020/
	export PYTHONPATH=./lib/
	python setup.py develop -d ./lib/

which completes its install fine, although ive found if you run the  
exact same command a second time, you get the error "Too many open  
files", until you go and delete the files setuptools created.   
anyway, if I run python and look at sys.path, my local "./lib"  
version is still after the site-packages "egg" version; this is  
confirmed if i "import sqlalchemy" and look at its __file__; its  
still on the site-packages one.  so it essentially is not working  
(not the way im expecting, at least).

the only way I can get it to work is like this:

	sudo python setup.py develop

which overrides the site-packages version, but also requires root  
access.  how would I do this without requiring root access ?