There are 3 shapes on a 3x3 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 (1, 1)
Distance from target shape to blue square at (1, 2): 1
Distance from target shape to gray square at (0, 1): 1
Closest shape is the blue square at (1, 2) with distance 1</think>

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