Typing hints the component library

[rainzee]

Abstract & Motivation

Using Python Type Hint syntaxit will bring many benefits, the most direct of which is more powerful IDE support and intelligent perception, while also reducing various bugs and making the component library more robust. refer to:

• typing
• PEP 484
• PEP 526

Implementation

We will achieve our goals through a series of progressive PRs

• use typing-extensions avoid low version dependency issues
• impl typing module
• Gradually abstract away type aliases
• Adding type annotations incrementally