Caching

• cached-property: A decorator for caching properties in classes.
• cachetools: This module provides various memoizing collections and decorators.

Parallel Computing

• deco: A simplified parallel computing model for Python. DECO automatically parallelizes Python programs.

Function Signatures

• decorator: This is your best option if you want to preserve the signature of decorated functions in a consistent way across Python releases.

Deprecating Code

• deprecated: Use @deprecated decorator to deprecate old python classes, functions or methods.

Command Line Interfaces

• click: Click is a Python package for creating beautiful command line interfaces, based on declaring commands through decorators.

Locking

• fasteners: Provides useful locks and decorators to lock/unlock around functions and methods.

Web Frameworks

• flask: Flask is a micro web framework in python, which uses decorators to route the URL, register error handler, register processor and so on.
• flask-login: Flask-Login provides user session management for Flask. For example, it use the login_required decorator to protect some views that need the user to be logged in.

API Development

• me-api: An extensible, personal API with custom integrations. It uses a decorator to make sure there is an access_token in the configuration file before sending the API request and reject another authentication if there is already an access_token.

Performance Optimization

• numba: Numba gives you the power to speed up your applications with high performance functions written directly in Python. It uses jit to decorate array-oriented and math-heavy Python code can be just-in-time compiled to native machine instructions.