def test_drop_obs_column():
    adata = ad.AnnData(np.array(X_list), obs=obs_dict, dtype="int32")

    subset = adata[:2]
    assert subset.is_view
    # returns a copy of obs
    assert subset.obs.drop(columns=["oanno1"]).columns.tolist() == ["oanno2", "oanno3"]
    assert subset.is_view
    # would modify obs, so it should actualize subset and not modify adata
    subset.obs.drop(columns=["oanno1"], inplace=True)
    assert not subset.is_view
    assert subset.obs.columns.tolist() == ["oanno2", "oanno3"]

    assert adata.obs.columns.tolist() == ["oanno1", "oanno2", "oanno3"]
def _split_vertical(container):
		r1 = None
		r2 = None
		min_w = int(W_RATIO*container.h)+1
		if container.w < 2*min_w:
			return None
		r1 = Container(container.x,container.y,randint(min_w, container.w-min_w),container.h)
		r2 = Container(container.x+r1.w,container.y,container.w-r1.w,container.h)
		return [r1, r2]