code: def find_tarball(directory, name, version):
      
      dir_contents = os.listdir(os.path.join(directory, 'dist'))
      candidates = [tarball for tarball in dir_contents
                    if tarball.endswith('.gz')
                    and tarball.startswith(name + '-' + version)]
      if not candidates:
          logger.error("No recognizable distribution found for %s, version %s",
                       name, version)
          logger.error("Contents of %s: %r", directory, dir_contents)
          return
      if len(candidates) > 1:
          # Should not happen.
          logger.warn("More than one candidate distribution found: %r",
                      candidates)
      tarball = candidates[0]
      return os.path.join(directory, 'dist', tarball)
docs: Return matching tarball filename from dist/ dir (if found).
  
      Setuptools generates a source distribution in a ``dist/`` directory and we
      need to find the exact filename, whether .tgz or .zip.
  
      We expect "name + '-' + version + '.tar.gz'", but we *can* get a
      -dev.r1234.tar.gz as that can be configured in a setup.cfg.  Not pretty,
      but we don't want to force anyone to modify old tags.