There are 5 shapes on a 7x7 grid. Which shape is closest to the purple 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: purple trapezoid at (6, 4)
Distance from target shape to gray right_triangle at (2, 1): 7
Distance from target shape to blue trapezoid at (1, 5): 6
Distance from target shape to red trapezoid at (4, 3): 3
Distance from target shape to pink square at (0, 6): 8
Closest shape is the red trapezoid at (4, 3) with distance 3</think>

<answer>(4, 3)</answer>