There are 6 shapes on a 6x6 grid. Which shape is closest to the blue 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: blue right_triangle at (4, 0)
Distance from target shape to brown right_triangle at (1, 0): 3
Distance from target shape to cyan rectangle at (0, 3): 7
Distance from target shape to green right_triangle at (4, 4): 4
Distance from target shape to yellow trapezoid at (5, 5): 6
Distance from target shape to gray trapezoid at (5, 3): 4
Closest shape is the brown right_triangle at (1, 0) with distance 3</think>

<answer>(1, 0)</answer>