red_filter, copying

Define red_filter function that takes a 2D list img as its parameter. The function has to maintain the R components of img but reduce its G, B components all as 0. Define the function so that it returns a copy of the inputted img. The input img itself should not change at all.

Sample Input 1:

[[(255, 0, 0), (0, 255, 0), (0, 0, 255)], [(255, 0, 0), (0, 255, 0), (0, 0, 255)], [(255, 0, 0), (0, 255, 0), (0, 0, 255)]]

Sample Output 1:

[[(255, 0, 0), (0, 0, 0), (0, 0, 0)], [(255, 0, 0), (0, 0, 0), (0, 0, 0)], [(255, 0, 0), (0, 0, 0), (0, 0, 0)]]

Sample Input 2:

[[(1, 2, 3), (4, 5, 6)], [(7, 8, 9), (10, 11, 12)], [(13, 14, 15), (16, 17, 18)], [(19, 20, 21), (22, 23, 24)], [(25, 26, 27), (28, 29, 30)]]

Sample Output 2:

[[(1, 0, 0), (4, 0, 0)], [(7, 0, 0), (10, 0, 0)], [(13, 0, 0), (16, 0, 0)], [(19, 0, 0), (22, 0, 0)], [(25, 0, 0), (28, 0, 0)]]