# Public Gist

This is a public gist on my self host gist site.

```python
# Factorial Function
def factorial(n: int) -> int:
   ''' Factorial, returns `n!`. Equal to `1*2*3*...n`.
    if n < 0:
        raise ArgumentError("factorial invalid for negative values")
    if n <= 1:
        return 1
    return n * factorial(n - 1)
```

Over.