numpy dummy variables code example

Example: getting dummies and input them to pandas dataframe

note:
dummies = pd.get_dummies(df[['column_1']], drop_first=True)
df = pd.concat([df.drop(['column_1'],axis=1), dummies],axis=1)


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)
df = pd.concat([df.drop(['column_1', 'column_1'],axis=1), dummies],axis=1)