~$ sudo -H pip install --upgrade pip 
Collecting pip
  Downloading pip-9.0.1-py2.py3-none-any.whl (1.3MB)
    100% |████████████████████████████████| 1.3MB 75kB/s 
Installing collected packages: pip
  Found existing installation: pip 8.1.1
    Not uninstalling pip at /usr/lib/python2.7/dist-packages, outside environment /usr
Successfully installed pip-9.0.1
~$ pip install dbus
Collecting dbus
  Could not find a version that satisfies the requirement dbus (from versions: )
No matching distribution found for dbus