There are 5 shapes on a 7x7 grid. Which shape is closest to the blue 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: blue rectangle at (4, 0)
Distance from target shape to red trapezoid at (2, 4): 6
Distance from target shape to cyan trapezoid at (0, 2): 6
Distance from target shape to purple right_triangle at (1, 5): 8
Distance from target shape to brown rectangle at (6, 2): 4
Closest shape is the brown rectangle at (6, 2) with distance 4</think>

<answer>(6, 2)</answer>