There are 6 shapes on a 6x6 grid. Which shape is closest to the gray 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: gray square at (1, 3)
Distance from target shape to blue right_triangle at (3, 5): 4
Distance from target shape to purple right_triangle at (2, 2): 2
Distance from target shape to cyan square at (5, 3): 4
Distance from target shape to orange trapezoid at (3, 0): 5
Distance from target shape to pink trapezoid at (0, 2): 2
Closest shape is the purple right_triangle at (2, 2) with distance 2</think>

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