= Online Linear Regression

Implement online linear regression using only python standard library and numpy. From numpy only elementary operations are allowed (addition, multiplication, indexing,...), definitely not something from numpy.linalg. Preferred solution is to use QR decomposition, however, any other algorithm with similar or better complexity is accepted and appreciated.

Your implementation should have the following interface:

[source,python]

class LinearRegression:

    def fit(self, X: Tuple[float], y: float) -> LinearRegression:
        ...
    def predict(self, X: Tuple[float]) -> float:
        ...