@classmethod
    def _clear(cls):
        cls._default_depot = None
        cls._depots = {}
        cls._middleware = None
        cls._aliases = {}
Builds the entire tree.  Returns the number of failures.
dataset/ETHPy150Open amol-/depot/depot/manager.py/DepotManager._clear--crossover with--dataset/ETHPy150Open lektor/lektor/lektor/builder.py/Builder.build_all