There are 6 shapes on a 8x8 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 (2, 2)
Distance from target shape to blue square at (0, 7): 7
Distance from target shape to red square at (6, 4): 6
Distance from target shape to yellow trapezoid at (2, 1): 1
Distance from target shape to green right_triangle at (7, 4): 7
Distance from target shape to gray right_triangle at (1, 7): 6
Closest shape is the yellow trapezoid at (2, 1) with distance 1</think>

<answer>(2, 1)</answer>