There are 5 shapes on a 8x8 grid. Which shape is closest to the red 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: red right_triangle at (2, 6)
Distance from target shape to blue trapezoid at (3, 0): 7
Distance from target shape to green rectangle at (1, 5): 2
Distance from target shape to yellow trapezoid at (1, 7): 2
Distance from target shape to brown square at (4, 3): 5
Closest shape is the green rectangle at (1, 5) with distance 2</think>

<answer>(1, 5)</answer>