There are 3 shapes on a 7x7 grid. Which shape is closest to the purple 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: purple right_triangle at (1, 4)
Distance from target shape to pink square at (0, 6): 3
Distance from target shape to gray right_triangle at (6, 0): 9
Closest shape is the pink square at (0, 6) with distance 3</think>

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