如何在atool-build的webpack配置文件中，添加新plugin？

[SSebo]

webpackConfig.plugins.push(
    new webpack.DefinePlugin({
      __DEV__: JSON.stringify(JSON.parse(process.env.BUILD_DEV || 'true')),
      __PRERELEASE__: JSON.stringify(JSON.parse(process.env.BUILD_PRERELEASE || 'false'))
    })
  );

会报错，说webpack not defined

[sorrycc]

var webpack = require('atool-build/lib/webpack');

[SSebo]

非常感谢