Please reason step by step, and put your final answer within \boxed{}.
Find the point $O$ inside the triangle $ABC$ that satisfies the following property: for any line passing through $O$ and intersecting side $AB$ at point $K$ and side $BC$ at point $L$, the equality $p \frac{A K}{K B} + q \frac{C L}{L B} = 1$ holds, where $p$ and $q$ are given positive numbers.
user