There are 6 shapes on a 6x6 grid. Which shape is closest to the green rectangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: green rectangle at (5, 0)
Distance from target shape to purple right_triangle at (5, 2): 2
Distance from target shape to orange rectangle at (5, 1): 1
Distance from target shape to gray right_triangle at (3, 0): 2
Distance from target shape to yellow right_triangle at (1, 2): 6
Distance from target shape to brown square at (4, 5): 6
Closest shape is the orange rectangle at (5, 1) with distance 1</think>

<answer>(5, 1)</answer>