A downgrade package using pip creates a ValueError ("Expected specification version in",

Question

On a Ubuntu 12.04 system, where I don't have sudo privileges, I set up a virtual environment to have updated python packages. The virtualenv system installed a rather old version of pip (1.1) on it, which I upgraded to 6.1.1.

Now I find that if I try to specify a package version with something like:

pip install pymongo=2.6.2 

pip throws a ValueError ("Expected specification version in", "pymongo = 2.6.2", "at", "= 2.6.2")

Answer 1

The syntax for specifying the version is package==versionSpec with two equal signs, so I had to do:

 pip install pymongo==2.6.2