def METHOD_NAME(mask_model):
    mask_model._mask_data[4, 4] = 1
    mask_model._mask_data[0, 0] = 1
    mask_model._mask_data[0, 9] = 1
    mask_model._mask_data[9, 9] = 1
    mask_model._mask_data[9, 0] = 1
    mask_model.grow()
    # tests corners
    assert mask_model._mask_data[0, 1] == 1
    assert mask_model._mask_data[1, 1] == 1
    assert mask_model._mask_data[1, 0] == 1
    assert mask_model._mask_data[0, 8] == 1
    assert mask_model._mask_data[1, 8] == 1
    assert mask_model._mask_data[1, 9] == 1
    assert mask_model._mask_data[8, 0] == 1
    assert mask_model._mask_data[8, 1] == 1
    assert mask_model._mask_data[9, 1] == 1
    assert mask_model._mask_data[8, 8] == 1
    assert mask_model._mask_data[8, 9] == 1
    assert mask_model._mask_data[9, 8] == 1
    # tests center
    assert mask_model._mask_data[3, 3] == 1
    assert mask_model._mask_data[4, 3] == 1
    assert mask_model._mask_data[5, 3] == 1
    assert mask_model._mask_data[3, 5] == 1
    assert mask_model._mask_data[4, 5] == 1
    assert mask_model._mask_data[5, 5] == 1
    assert mask_model._mask_data[3, 4] == 1
    assert mask_model._mask_data[5, 4] == 1