This method is deprecated or moved on the latest stable version.
The last existing version (v2_2_9) is shown here.
lookup(task_name, initial_scope=nil)
public
Lookup a task, using scope and the scope hints in the task name. This
method performs straight lookups without trying to synthesize file tasks or rules. Special scope
names (e.g. ‘^’) are recognized. If no scope argument is supplied, use
the current scope. Return nil if the task cannot be found.