df.rename(columns={'oldName1': 'newName1',
                   'oldName2': 'newName2'},
          inplace=True, errors='raise')
# Make sure you set inplace to True if you want the change
# to be applied to the dataframe

df_new = df.rename(columns={'A': 'a'}) #change a from A

import pandas as pd
data = pd.read_csv(file)
data.rename(columns={'original':'new_name'}, inplace=True)

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

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

>>> 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