There are 4 shapes on a 8x8 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 (7, 5)
Distance from target shape to blue rectangle at (4, 7): 5
Distance from target shape to cyan square at (5, 6): 3
Distance from target shape to purple right_triangle at (5, 3): 4
Closest shape is the cyan square at (5, 6) with distance 3</think>

<answer>(5, 6)</answer>