def is_intersection_line_line_xy(l1, l2, tol=1e-06):
    """Verifies if two lines intersect on the XY-plane.

    Parameters
    ----------
    l1 : tuple
        A sequence of XYZ coordinates of two 3D points representing two points on the line.
    l2 : tuple
        A sequence of XYZ coordinates of two 3D points representing two points on the line.
    tol : float, optional
        A tolerance for intersection verification. Default is ``1e-6``.

    Returns
    --------
    bool
        ``True``if the lines intersect in one point
        ``False`` if the lines are skew, parallel or lie on top of each other.
    """
    raise NotImplementedError
