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

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