code: def mirror_file(self, path_to, path_from, from_quick_server=True):
          
          full_path = path_from if not from_quick_server else os.path.join(
              os.path.dirname(__file__), path_from)
          if self._mirror is None:
              if not self._symlink_mirror(path_to, full_path, init=True):
                  self._poll_mirror(path_to, full_path, init=True)
              return
          impl = self._mirror["impl"]
          if impl == "symlink":
              self._symlink_mirror(path_to, full_path, init=False)
          elif impl == "poll":
              self._poll_mirror(path_to, full_path, init=False)
          else:
              raise ValueError("unknown mirror implementation: {0}".format(impl))
docs: Mirrors a file to a different location. Each time the file changes
             while the process is running it will be copied to 'path_to',
             overwriting the destination.
  
          Parameters
          ----------
          path_to : string
              The mirror destination.
  
          path_from : string
              The mirror origin.
  
          from_quick_server : bool
              If set the origin path is relative to *this* script otherwise it is
              relative to the process.