There are 6 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 (1, 3)
Distance from target shape to green trapezoid at (5, 0): 7
Distance from target shape to blue trapezoid at (2, 3): 1
Distance from target shape to red rectangle at (1, 2): 1
Distance from target shape to brown rectangle at (0, 5): 3
Distance from target shape to purple square at (5, 4): 5
Closest shape is the blue trapezoid at (2, 3) with distance 1</think>

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