import numpy as np
def get_bayer_masks(n_rows, n_cols):
    R = [[0, 1], [0, 0]]
    G = [[1, 0], [0, 1]]
    B = [[0, 0], [1, 0]]
    return np.stack(
    	[
    	np.tile(R, ((n_rows + 1)//2, (n_cols + 1)//2))[:n_rows,:n_cols],
    	np.tile(G, ((n_rows + 1)//2, (n_cols + 1)//2))[:n_rows,:n_cols],
    	np.tile(B, ((n_rows + 1)//2, (n_cols + 1)//2))[:n_rows,:n_cols]
    	],
    	axis = 2
    )
def get_colored_img(raw_img):
    masks = get_bayer_masks(*raw_img.shape)
    return np.stack(
   	[
    	raw_img*masks[...,0],
    	raw_img*masks[...,1],
    	raw_img*masks[...,2]
   	],
    	axis = 2
    )