codexia

### Suggested Code Snippet

```python
# Sample Python function to calculate the factorial of a number

def factorial(n):
    if n == 0:
        return 1
    else:
        return n * factorial(n-1)

# Example usage
print(factorial(5))  # Output: 120
```

### Explanation
- **Functionality**: This function calculates the factorial of a given number using recursion.
- **Usage**: You can call `factorial(5)` to get the result of `5!` which is `120`.