There are 6 shapes on a 8x8 grid. Which shape is closest to the brown 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: brown right_triangle at (0, 6)
Distance from target shape to yellow right_triangle at (5, 3): 8
Distance from target shape to gray square at (2, 0): 8
Distance from target shape to orange rectangle at (4, 0): 10
Distance from target shape to blue square at (4, 5): 5
Distance from target shape to cyan rectangle at (7, 3): 10
Closest shape is the blue square at (4, 5) with distance 5</think>

<answer>(4, 5)</answer>