get dummies pandas

                                    note:
dummies = pd.get_dummies(df[['column_1']], drop_first=True)

note:for more that one coloum keep ading in the list 
dummies = pd.get_dummies(df[['column_1', 'column_2','column_3']], drop_first=True)

                                    >>> s = pd.Series(list('abca'))

>>> pd.get_dummies(s)
   a  b  c
0  1  0  0
1  0  1  0
2  0  0  1
3  1  0  0

                                    >>> pd.get_dummies(pd.Series(list('abcaa')), drop_first=True)
   b  c
0  0  0
1  1  0
2  0  1
3  0  0
4  0  0

                                    df = pd.get_dummies(df, columns=['type'])

                                    >>> pd.get_dummies(pd.Series(list('abc')), dtype=float)
     a    b    c
0  1.0  0.0  0.0
1  0.0  1.0  0.0
2  0.0  0.0  1.0