https://realpython.com/python-shebang
In this tutorial, you’ll:
- Learn what a shebang is
- Decide when to include the shebang in Python scripts
- Define the shebang in a portable way across systems
- Pass arguments to the command defined in a shebang
- Know the shebang’s limitations and some of its alternatives
- Execute scripts through a custom interpreter written in Python
In short, a shebang is a special kind of comment that you may include in your source code to tell the operating system’s shell where to find the interpreter for the rest of the file:
#!/usr/bin/python3
print("Hello, World!")