There are 3 shapes on a 6x6 grid. Which shape is closest to the orange rectangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: orange rectangle at (5, 3)
Distance from target shape to green square at (3, 3): 2
Distance from target shape to red right_triangle at (3, 5): 4
Closest shape is the green square at (3, 3) with distance 2</think>

<answer>(3, 3)</answer>