There are 3 shapes on a 7x7 grid. Which shape is closest to the red trapezoid 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 trapezoid at (1, 6)
Distance from target shape to blue square at (3, 0): 8
Distance from target shape to green trapezoid at (3, 5): 3
Closest shape is the green trapezoid at (3, 5) with distance 3</think>

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