There are 3 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 (5, 4)
Distance from target shape to red trapezoid at (3, 1): 5
Distance from target shape to blue square at (0, 0): 9
Closest shape is the red trapezoid at (3, 1) with distance 5</think>

<answer>(3, 1)</answer>