There are 5 shapes on a 10x10 grid. Which shape is closest to the purple 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: purple rectangle at (7, 9)
Distance from target shape to cyan trapezoid at (0, 0): 16
Distance from target shape to orange right_triangle at (3, 0): 13
Distance from target shape to red right_triangle at (1, 4): 11
Distance from target shape to gray rectangle at (6, 3): 7
Closest shape is the gray rectangle at (6, 3) with distance 7</think>

<answer>(6, 3)</answer>