There are 6 shapes on a 6x6 grid. Which shape is closest to the pink 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: pink square at (5, 3)
Distance from target shape to brown right_triangle at (1, 1): 6
Distance from target shape to green rectangle at (1, 0): 7
Distance from target shape to orange right_triangle at (3, 1): 4
Distance from target shape to red square at (2, 1): 5
Distance from target shape to blue trapezoid at (3, 0): 5
Closest shape is the orange right_triangle at (3, 1) with distance 4</think>

<answer>(3, 1)</answer>