There are 4 shapes on a 7x7 grid. Which shape is closest to the yellow right_triangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: yellow right_triangle at (5, 3)
Distance from target shape to gray trapezoid at (2, 1): 5
Distance from target shape to cyan trapezoid at (0, 2): 6
Distance from target shape to blue rectangle at (2, 3): 3
Closest shape is the blue rectangle at (2, 3) with distance 3</think>

<answer>(2, 3)</answer>