Installing "Glances" system monitor on ubuntu 12.04

Glances is a curses based tool for monitoring your system - kind of like top on steroids. There is a small issue with using the version in the PPA on Ubuntu 12.04 (specifically the 12.04.2 minimal install); it crashes on startup with the following error:

Traceback (most recent call last):
  File "/usr/bin/glances", line 5, in
    from pkg_resources import load_entry_point
ImportError: No module named pkg_resources

To fix it I manually had to install the package python-pkg-resources.