Python Comments & Shebang

Syntax Satellite

Comments & Shebang

Communicate intent to humans with comments/docstrings and to the OS with shebang lines.

Write effective commentsUse shebangs

Comments

• Single-line: # explain why, not what
• Block: stack single-line comments or use docstrings
• Avoid redundant comments; focus on intent, edge cases, or references.

Docstrings

def fetch_user(user_id: str) -> dict:
    """Retrieve a user profile from the API by ID."""

Use triple quotes. Tools like Sphinx or MkDocs can generate documentation from docstrings.

Shebang

#!/usr/bin/env python3

• Place at the top of executable scripts.
• Run chmod +x script.py and execute ./script.py.
• Uses env to locate the correct interpreter on the PATH.

Next up in your learning path

Syntax guide

See how comments integrate with indentation and keywords.

Companion

Run scripts

Pair shebang knowledge with CLI execution.

Practical

Docstrings + type hints

Use both to document functions thoroughly.

Advanced