rename a column dataframe which already doesn not have a name code example

Example 1: rename column name pandas dataframe

df.rename(columns={"old_col1": "new_col1", "old_col2": "new_col2"})

Example 2: dataframe rename column

>>> 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