Store the arguments as public members

Question

in python, what is the meaning of "Store the pattern in the public member output and return a copy"?

for example how can I create a copy from this class?

class Checker():

    def __init__(self,resolution,tile_size):
        self.resolution=resolution
        self.tile_size=tile_size
        if np.mod(resolution, tile_size) != 0 :
            raise ValueError(' resolution that are evenly dividable by 2· tile size ')
        else:
            self.mult=int(resolution/(tile_size*2))

    def draw(self):
        bl_tile= np.zeros((self.tile_size,self.tile_size))
        wh_tile= np.ones_like(bl_tile)
        wb_matrix1=np.concatenate((bl_tile,wh_tile),axis=1)
        wb_matrix2=np.concatenate((wh_tile,bl_tile),axis=1)
        wb_matrix=np.concatenate((wb_matrix1,wb_matrix2),axis=0)
        self.output=np.tile(wb_matrix,(self.mult,self.mult))
        return self.output