5. On a plane, 2007 non-coincident lines $l_{1}, l_{2}, \cdots, l_{2007}$ are drawn, always following the rule of alternating perpendicular and parallel $\left(l_{2} \perp l_{1}, l_{3} / / l_{2}, l_{4} \perp l_{3}, l_{5} / /\right.$ $\left.l_{4}, \cdots\right)$. These 2007 non-coincident lines have a total of intersection points.
5.
$$
1007012
$$