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

<answer>(0, 2)</answer>