```python
import numpy as np
def make_array(value):
return np.full((50, 50, 1), value, dtype=np.uint8)
def setup():
global img
py5.image_mode(py5.CENTER)
img = py5.create_image(50, 50, py5.RGB)
def draw():
py5.background(128)
array = make_array(py5.frame_count % 256)
img.set_np_pixels(array, bands='L')
py5.image(img, py5.mouse_x, py5.mouse_y)
```