code: def read_git_blob(commit_ref, path, repo_dir='.'):
      
      repo = git.Repo(repo_dir)
      tree = repo.tree(commit_ref)
      dirname, fname = os.path.split(path)
      text = None
      if dirname == '':
          text = _read_blob(tree, fname)
      else:
          components = path.split(os.sep)
          text = _read_blob_in_tree(tree, components)
      return text
docs: Get text from a git blob.
  
      Parameters
      ----------
      commit_ref : str
          Any SHA or git tag that can resolve into a commit in the
          git repository.
      path : str
          Path to the document in the git repository, relative to the root
          of the repository.
      repo_dir : str
          Path from current working directory to the root of the git repository.
  
      Returns
      -------
      text : unicode
          The document text.