There are 6 shapes on a 8x8 grid. Which shape is closest to the green 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: green rectangle at (3, 2)
Distance from target shape to yellow trapezoid at (3, 1): 1
Distance from target shape to orange trapezoid at (1, 7): 7
Distance from target shape to brown rectangle at (2, 6): 5
Distance from target shape to gray trapezoid at (1, 4): 4
Distance from target shape to pink rectangle at (7, 6): 8
Closest shape is the yellow trapezoid at (3, 1) with distance 1</think>

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