pandas can't rename column code example

Example 1: rename column pandas

>>> df = pd.DataFrame({"A": [1, 2, 3], "B": [4, 5, 6]})
>>> df.rename(columns={"A": "a", "B": "c"})
   a  c
0  1  4
1  2  5
2  3  6

Example 2: how to change column name in pandas

print(df.rename(columns={'A': 'a', 'C': 'c'}))
#         a   B   c
# ONE    11  12  13
# TWO    21  22  23
# THREE  31  32  33