There are 5 shapes on a 7x7 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, 5)
Distance from target shape to gray right_triangle at (1, 6): 2
Distance from target shape to yellow rectangle at (0, 1): 4
Distance from target shape to cyan trapezoid at (5, 6): 6
Distance from target shape to blue square at (6, 4): 7
Closest shape is the gray right_triangle at (1, 6) with distance 2</think>

<answer>(1, 6)</answer>