When I do a pip freeze I see large number of Python packages that I didn\'t explicitly install, e.g.
$ pip freeze Cheetah==2.4.3 GnuPGInterface==0.3.2 Landsc
The pip show command will show what packages are required for the specified package (note that the specified package must already be installed):
pip show
$ pip show specloud Package: specloud Version: 0.4.4 Requires: nose figleaf pinocchio
pip show was introduced in pip version 1.4rc5