encountered a problem and simplified it.
has a dataframe
df = pd.DataFrame([["a", 1, "c"], ["a", 3, "a"], ["a", 2, "b"],
["c", 3, "a"], ["c", 2, "b"], ["c", 1, "c"],
["b", 2, "b"], ["b", 3, "a"], ["b",1, "c"]], columns=["A", "B", "C"])
AB
, , A,A, ()
:
and the parameter by the order of list elements is the order by which column you sort first
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