There are 5 shapes on a 7x7 grid. Which shape is closest to the yellow rectangle 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 rectangle at (2, 1)
Distance from target shape to pink trapezoid at (0, 5): 6
Distance from target shape to cyan right_triangle at (5, 6): 8
Distance from target shape to purple rectangle at (1, 4): 4
Distance from target shape to gray rectangle at (2, 5): 4
Closest shape is the purple rectangle at (1, 4) with distance 4</think>

<answer>(1, 4)</answer>