There are 6 shapes on a 6x6 grid. Which shape is closest to the green 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: green right_triangle at (0, 1)
Distance from target shape to orange square at (1, 2): 2
Distance from target shape to yellow square at (5, 5): 9
Distance from target shape to purple rectangle at (0, 0): 1
Distance from target shape to red rectangle at (3, 4): 6
Distance from target shape to pink right_triangle at (2, 4): 5
Closest shape is the purple rectangle at (0, 0) with distance 1</think>

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