docs: def jinja_env(template_path):
      """Sets up our Jinja environment, loading the few filters we have"""
      fs_loader = FileSystemLoader(os.path.dirname(template_path))
      env = Environment(loader=fs_loader,
                        autoescape=True,
                        trim_blocks=True,
                        lstrip_blocks=True)
      env.filters['b64encode'] = portable_b64encode
      env.filters['b64decode'] = f_b64decode
      return env