There are 6 shapes on a 7x7 grid. Which shape is closest to the pink 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: pink rectangle at (3, 1)
Distance from target shape to green trapezoid at (5, 3): 4
Distance from target shape to purple square at (0, 6): 8
Distance from target shape to blue rectangle at (2, 4): 4
Distance from target shape to yellow rectangle at (5, 1): 2
Distance from target shape to cyan right_triangle at (0, 0): 4
Closest shape is the yellow rectangle at (5, 1) with distance 2</think>

<answer>(5, 1)</answer>