code: def deep_dependendants(self, target):
          
          direct_dependents = self._gettask(target).provides_for
  
          return (direct_dependents +
                  reduce(
                      lambda a, b: a + b,
                      [self.deep_dependendants(x) for x in direct_dependents],
                      []))
docs: Recursively finds the dependents of a given build target.
              Assumes the dependency graph is noncyclic