@abstractmethod
  def _isfile_raw(self, relpath):
Attempts to connect to the child process.
dataset/ETHPy150Open pantsbuild/pants/src/python/pants/base/project_tree.py/ProjectTree._isfile_raw--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/tools/dev_appserver_multiprocess.py/ChildProcess.Connect