There are 6 shapes on a 8x8 grid. Which shape is closest to the pink right_triangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: pink right_triangle at (1, 7)
Distance from target shape to purple rectangle at (7, 0): 13
Distance from target shape to red square at (4, 5): 5
Distance from target shape to gray trapezoid at (2, 2): 6
Distance from target shape to yellow right_triangle at (3, 1): 8
Distance from target shape to green rectangle at (0, 6): 2
Closest shape is the green rectangle at (0, 6) with distance 2</think>

<answer>(0, 6)</answer>