There are 5 shapes on a 4x4 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 brown rectangle at (2, 0): 2
Distance from target shape to pink right_triangle at (1, 2): 3
Distance from target shape to blue square at (3, 0): 3
Distance from target shape to yellow square at (3, 2): 5
Closest shape is the brown rectangle at (2, 0) with distance 2</think>

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