Sources for self-learning

• LearnPython.org:

  • http://learnpython.org/en/Decorators

  • http://learnpython.org/en/Exception_Handling

• Habrahabr:

  • http://habrahabr.ru/post/141411/

• Top 6 Django decorators:

  • https://www.bedjango.com/blog/top-6-django-decorators/