There are 4 shapes on a 6x6 grid. Which shape is closest to the orange square 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 square at (4, 3)
Distance from target shape to brown square at (2, 0): 5
Distance from target shape to purple square at (2, 4): 3
Distance from target shape to red right_triangle at (5, 3): 1
Closest shape is the red right_triangle at (5, 3) with distance 1</think>

<answer>(5, 3)</answer>