There are 3 shapes on a 7x7 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 (1, 1)
Distance from target shape to red trapezoid at (4, 4): 6
Distance from target shape to gray square at (1, 6): 5
Closest shape is the gray square at (1, 6) with distance 5</think>

<answer>(1, 6)</answer>