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 pop(self, key, default=None):
        value = self._collection.pop(key, default)
        return self._to_python(value)