docs: def upload(branch, user, tool):
      """
      Commit + push to branch
      Returns username, commit hash
      """
      with ProgressBar(_("Uploading")):
          language = os.environ.get("LANGUAGE")
          commit_message = [_("automated commit by {}").format(tool)]
  
          # If LANGUAGE environment variable is set, we need to communicate
          # this to any remote tool via the commit message.
          if language:
              commit_message.append(f"[{language}]")
  
          commit_message = " ".join(commit_message)
  
          # Commit + push
          git = Git(Git.working_area)
          _run(git(f"commit -m {shlex.quote(commit_message)} --allow-empty"))
          _run(git.set(Git.cache)(f"push origin {branch}"))
          commit_hash = _run(git("rev-parse HEAD"))
          return user.name, commit_hash