code: def _add_form_fields(obj, lines):
      
      lines.append("**Form fields:**")
      lines.append("")
      for name, field in obj.base_fields.items():
          field_type = "{}.{}".format(field.__class__.__module__, field.__class__.__name__)
          tpl = "* ``{name}``: {label} (:class:`~{field_type}`)"
          lines.append(tpl.format(
              name=name,
              field=field,
              label=field.label or name.replace('_', ' ').title(),
              field_type=field_type
          ))
docs: Improve the documentation of a Django Form class.
  
      This highlights the available fields in the form.