update readme

Author: michael-yin

README.md

@@ -23,6 +23,14 @@ When using `django-webpack-loader`, you need to create `Webpack` project on your
 - Autoprefixing of browserspecific CSS rules via [postcss](https://postcss.org/) and [postcss-preset-env](https://github.com/csstools/postcss-preset-env)
 - Style Linting via [stylelint](https://stylelint.io/)
 
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+If you want to import **lightweight modern frontend solution** to your web app, or you do not like **heavy framework** such as React, Vue.
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+Please check my book [The Definitive Guide to Hotwire and Django](https://leanpub.com/hotwire-django)
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+----
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 ## Documentation
 
 1. [Setup With Django](https://python-webpack-boilerplate.readthedocs.io/en/latest/setup_with_django/)