def adata():
    adata = ad.AnnData(np.zeros((100, 100)))
    adata.obsm["o"] = np.zeros((100, 50))
    adata.varm["o"] = np.zeros((100, 50))
    return adata
def reorder_item(self, item, position):
    new_position = min(max(position, 0), len(self._items) - 1)