In #47215 I brought up the issue of allowing sets as arguments for the DataFrame constructor. This was addressed in #47231 . But there are a few more cases that should be fixed:

>>> pd.Series([3,4,5], index=set(["a", "b", "c"])) c 3 a 4 b 5 dtype: int64 >>> pd.DataFrame.from_records([[1,2,3]], columns=set(["a", "b", "c"]), index=set(["x", "y", "z"])) c a b x 1 2 3 y 1 2 3 z 1 2 3

We shouldn't allow a set as an argument for index or columns in both these cases.