There are 5 shapes on a 6x6 grid. Which shape is closest to the blue right_triangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: blue right_triangle at (3, 5)
Distance from target shape to pink rectangle at (2, 4): 2
Distance from target shape to gray trapezoid at (1, 4): 3
Distance from target shape to cyan square at (5, 4): 3
Distance from target shape to green trapezoid at (2, 2): 4
Closest shape is the pink rectangle at (2, 4) with distance 2</think>

<answer>(2, 4)</answer>