_Framework.Disconnectable.Disconnectable:
Represents an entity that holds connections to other objects that
should be explicitly cleared to avoid object lifetime problems or
leaking listeners.
_Framework.Util.memoize:
Decorator to use automatic memoization on a given function, such
that results are chached and, if called a second time, the
function will return the cached value.
type:
type(object) -> the object's type type(name, bases, dict) ->
a new type