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

<answer>(3, 4)</answer>