Apply the Sobel operator to detect edges in an image. **Example:** For an image [[1, 2], [3, 4]], the output should be the edges detected by the Sobel operator. **Constraints:** The input image is a 2D numpy array, and the output should be a 2D numpy array with the same shape.
Test Cases
Test Case 1
Input:
[[1, 2], [3, 4]]Expected:
[[5.0, 5.0], [5.0, 5.0]]Test Case 2
Input:
[[1, 1], [1, 1]]Expected:
[[0.0, 0.0], [0.0, 0.0]]+ 3 hidden test cases