how to change a header in pandas

# Can just use df.columns to rename

>>> df = pd.DataFrame({'$a':[1,2], '$b': [10,20]})
>>> df.columns = ['a', 'b']
>>> df
   a   b
0  1  10
1  2  20

Here is what the above code is Doing:
1. Create a DataFrame with two columns, ‘$a’ and ‘$b’.
2. Rename the columns to ‘a’ and ‘b’.
3. Display the DataFrame.

Note that the ‘$’ signs are gone from the column names.