There are 3 shapes on a 9x9 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 (3, 7)
Distance from target shape to gray square at (5, 4): 5
Distance from target shape to brown trapezoid at (3, 5): 2
Closest shape is the brown trapezoid at (3, 5) with distance 2</think>

<answer>(3, 5)</answer>