TypeError: '<' not supported between instances of 'str' and 'int'

Question

I ran the below command -
print(np.unique(cars_data['Doors']))
Output -
['2' '3' '4' '5' 'five' 'four' 'three']
Then i ran below commands
cars_data['Doors'].replace('three',3,inplace=True)
cars_data['Doors'].replace('four',4,inplace=True)
cars_data['Doors'].replace('five',5,inplace=True)
And then whne i tried to print values again by -
print(np.unique(cars_data['Doors']))
I am getting error.

Answer 1

I have got the answer myself. We need to explicitly convert datatype to int64. And then i am getting the desired output.
cars_data['Doors']=cars_data['Doors'].astype('int64')