There are 5 shapes on a 5x5 grid. Which shape is closest to the green 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: green right_triangle at (3, 2)
Distance from target shape to brown right_triangle at (0, 1): 4
Distance from target shape to pink rectangle at (2, 0): 3
Distance from target shape to red square at (1, 2): 2
Distance from target shape to purple square at (4, 1): 2
Closest shape is the red square at (1, 2) with distance 2</think>

<answer>(1, 2)</answer>