_isTopDepthInBody(node, body) {
    if (!body) return false;
    if (!Array.isArray(body)) return false;

    const parentNode = node.parent;
    if (['ExportDefaultDeclaration', 'ExportNamedDeclaration'].includes(parentNode.type)) {
      node = parentNode;
    }

    for (const _node of body) {
      if (node === _node) return true;
    }
    return false;
  }
judge node is top in body.
@param {ASTNode} node - target node.
@param {ASTNode[]} body - target body node.
@returns {boolean} if true, the node is top in body.
@private