I just check the GFM (Github Flavored Markdown) spec to confirm the latest alert syntax which you probably have knew yet from other sources.

On GitHub, they are displayed with distinctive colors and icons to indicate the significance of the content.

To add an alert, use a special blockquote line specifying the alert type, followed by the alert information in a standard blockquote. Five types of alerts are available:

> [!NOTE]
>
> Useful information that users should know, even when skimming
> content.

> [!TIP]
>
> Helpful advice for doing things better or more easily.

> [!IMPORTANT]
>
> Key information users need to know to achieve their goal.

> [!WARNING]
>
> Urgent info that needs immediate user attention to avoid
> problems.

> [!CAUTION]
>
> Advises about risks or negative outcomes of certain actions.

Besides that, the first time I know GFM could also render colors automatically! What's more ✨, it supports multiple color models:

• HEX: #0969DA
• RGB: rgb(9, 105, 218)
• HSL: hsl(212, 92%, 45%)

References:

1. GitHub Docs - Basic writing and formatting syntax: Alerts
2. GitHub Docs - Basic writing and formatting syntax: Supported Color Models

Instagram has introduced PEP-683 Immortal Objects to their Python codebase (custom Django and custom Python interpreter) and achieve improvements in both memory and CPU efficiency of handling our requests by reducing copy on writes.

Refs:

• Introducing Immortal Objects for Python
• lqhuang.io Note - PEP 683 – Immortal Objects, Using a Fixed Refcount