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 (2, 2)
Distance from target shape to brown trapezoid at (3, 5): 4
Distance from target shape to gray right_triangle at (4, 3): 3
Distance from target shape to orange right_triangle at (1, 5): 4
Distance from target shape to blue right_triangle at (0, 4): 4
Distance from target shape to yellow right_triangle at (4, 1): 3
Closest shape is the gray right_triangle at (4, 3) with distance 3</think>

<answer>(4, 3)</answer>