Compute variance of a list in Python

## Task Given a Python list of numbers (ints/floats), write code to compute its **variance**. ### Requirements - Input: `nums: list[float]` (length \(n\ge 1\)) - Clarify whether you are computing: - **Population variance**: \(\sigma^2 = \frac{1}{n}\sum_{i=1}^n (x_i-\bar{x})^2\), or - **Sample variance**: \(s^2 = \frac{1}{n-1}\sum_{i=1}^n (x_i-\bar{x})^2\) (requires \(n\ge 2\)) - Avoid using `numpy`/`pandas` unless explicitly allowed. - State time and space complexity. ### Follow-ups (optional) - Implement a numerically stable one-pass version. - Handle edge cases (empty list, single element, very large numbers).