There are 4 shapes on a 3x3 grid. Which shape is closest to the yellow 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: yellow square at (2, 1)
Distance from target shape to orange trapezoid at (0, 1): 2
Distance from target shape to blue trapezoid at (1, 2): 2
Distance from target shape to purple trapezoid at (1, 1): 1
Closest shape is the purple trapezoid at (1, 1) with distance 1</think>

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