code: def within_proj_dir(path='.'):
      # type: (Optional[str]) -> str
      
      curr_dir = os.getcwd()
  
      os.chdir(proj_path(path))
  
      yield
  
      os.chdir(curr_dir)
docs: Return an absolute path to the given project relative path.
  
      :param path:
          Project relative path that will be converted to the system wide absolute
          path.
      :return:
          Absolute path.