I would prefer to have this customizable in some way - the idea behind 
having a separate get_tracker method was to allow additional 
customisation (e.g. inherit from RequestDispatcher and override 
get_tracker or add additional initialisation in the derived class). This 
hardcoded call from __init__ makes it a lot harder to customise the 
behaviour (because your overriding get_tracker relies on additional 
initialization from your __init__).