def find(self, *args):
data = self._path_data<EOL>exfn = data['<STR_LIT>']<EOL>join = data['<STR_LIT>'].join<EOL>path = join(*args)<EOL>return path if exfn(path) else None<EOL>
pdir.find(paths...) is similar to to os.path.join(paths...) but it only yields the joined
  relative path if it can be found inside pdir; otherwise None is yielded. Note that this
  does not extract or download the path--it merely ensures that it exists.