Flask-JWT-Extended not only adds support for using JSON Web Tokens (JWT) to
Flask for protecting views, but also many helpful (and optional) features built
in to make working with JSON Web Tokens easier. These include:

  - Support for adding custom claims to JSON Web Tokens
  - Custom claims validation on received tokens
  - Creating tokens from complex objects or complex object from received tokens
  - Refresh tokens
  - Token freshness and separate view decorators to only allow fresh tokens
  - Token revoking/blacklisting
  - Storing tokens in cookies and CSRF protection