There are 6 shapes on a 3x3 grid. Which shape is closest to the red 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: red right_triangle at (0, 0)
Distance from target shape to cyan rectangle at (0, 2): 2
Distance from target shape to brown rectangle at (1, 1): 2
Distance from target shape to blue trapezoid at (1, 2): 3
Distance from target shape to yellow right_triangle at (2, 1): 3
Distance from target shape to green right_triangle at (0, 1): 1
Closest shape is the green right_triangle at (0, 1) with distance 1</think>

<answer>(0, 1)</answer>