Flask-Principal provides a very loose framework to tie in providers of two
 types of service, often located in different parts of a web application:
 .
  - Authentication providers
  - User information providers
 .
 For example, an authentication provider may be oauth, using Flask-OAuth and
 the user information may be stored in a relational database. Looseness of
 the framework is provided by using signals as the interface.
 .
 This is the Python 3 version of the package.