There are 5 shapes on a 7x7 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 (0, 6)
Distance from target shape to red rectangle at (4, 0): 10
Distance from target shape to cyan trapezoid at (6, 2): 10
Distance from target shape to purple rectangle at (6, 3): 9
Distance from target shape to yellow square at (3, 5): 4
Closest shape is the yellow square at (3, 5) with distance 4</think>

<answer>(3, 5)</answer>