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 spel(isa, with_axis=False, ax=0):
    """plot super elements of I7/ISA7 model
    Args:
      isa: Isa7 object
    """
    from matplotlib.patches import Polygon
    if ax == 0:
        ax = plt.gca()
    ax.set_aspect('equal')
    for se in isa.superelements:
        ax.add_patch(Polygon([n.xy
                              for nc in se.nodechains
                              for n in nc.nodes],
                             color=isa.color[se.color], lw=0))

    ax.autoscale(enable=True)
    if not with_axis:
        ax.axis('off')