Add docstring.
Add docstring.

AndyHuu/flocker,AndyHuu/flocker,hackday-profilers/flocker,AndyHuu/flocker,wallnerryan/flocker-profiles,agonzalezro/flocker,agonzalezro/flocker,agonzalezro/flocker,hackday-profilers/flocker,mbrukman/flocker,w4ngyi/flocker,mbrukman/flocker,w4ngyi/flocker,mbrukman/flocker,w4ngyi/flocker,wallnerryan/flocker-profiles,hackday-profilers/flocker,wallnerryan/flocker-profiles