There are 4 shapes on a 9x9 grid. Which shape is closest to the gray 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: gray square at (6, 1)
Distance from target shape to brown trapezoid at (6, 4): 3
Distance from target shape to yellow rectangle at (3, 7): 9
Distance from target shape to green right_triangle at (2, 2): 5
Closest shape is the brown trapezoid at (6, 4) with distance 3</think>

<answer>(6, 4)</answer>