code: def visit_root(self, _, children):
          
  
          resource = children[1]
          resource.is_root = True
          return resource
docs: The main node holding all the query.
  
          Arguments
          ---------
          _ (node) : parsimonious.nodes.Node.
          children : list
              - 0: for ``WS`` (whitespace): ``None``.
              - 1: for ``NAMED_RESOURCE``: an instance of a subclass of ``.resources.Resource``.
              - 2: for ``WS`` (whitespace): ``None``.
  
          Returns
          -------
          .resources.Resource
              An instance of a subclass of ``.resources.Resource``, with ``is_root`` set to ``True``.
  
          Example
          -------
  
          >>> data = DataQLParser(r'''
          ... foo
          ... ''', default_rule='ROOT').data
          >>> data
          <Field[foo] />
          >>> data.is_root
          True
          >>> data = DataQLParser(r'''
          ... bar[name]
          ... ''', default_rule='ROOT').data
          >>> data
          <List[bar]>
            <Field[name] />
          </List[bar]>
          >>> data.is_root
          True
          >>> data = DataQLParser(r'''
          ... baz{name}
          ... ''', default_rule='ROOT').data
          >>> data
          <Object[baz]>
            <Field[name] />
          </Object[baz]>
          >>> data.is_root
          True