code: def _download(self, force_overwrite=False, verbose=False):
          
          if not force_overwrite:
              # If the file is already there, we're done
              if os.path.isfile(self.filepath):
                  if verbose:
                      print(
                          "File already available at %s -- skipping"
                          % (self.filepath)
                      )
                  return False
          stream_download(self.URL, self.filepath, verbose=verbose)
          return True
docs: Download the file if it's not already there.
          We shouldn't *need* to overwrite; the xml is not supposed to update.