def add_vectors(vector_a, vector_b):
    """Add two vectors

    Parameters
    ----------
    vector_a : np.ndarray
        shape=(n, )
    vector_b : np.ndarray
        shape=(n, )

    Examples
    --------
    >>> a = np.array([1, 2, 3])
    >>> b = np.array([10, 20, 20])
    >>> add_vectors(a, b)
    [11, 22, 23]
    """
    return [a+b for a, b in zip(vector_a, vector_b)]