无法在js函数中使用axios

function fetchData() {
  return new Promise((resolve, reject) => {
    axios.get('https://api.example.com/data')
      .then(response => {
        resolve(response.data);
      })
      .catch(error => {
        reject(error);
      });
  });
}

fetchData()
  .then(data => {
    // 处理返回的数据
  })
  .catch(error => {
    // 处理错误
  });

async function fetchData() {
  try {
    const response = await axios.get('https://api.example.com/data');
    return response.data;
  } catch (error) {
    throw error;
  }
}

(async () => {
  try {
    const data = await fetchData();
    // 处理返回的数据
  } catch (error) {
    // 处理错误
  }
})();