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

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