I am trying to perform one-hot encoding on some categorical columns. From the tutorial I am following, I am supposed to do LabelEncoding before One hot encoding. I have successfully performed the labelencoding as shown below

```
#categorical data
categorical_cols = ['a', 'b', 'c', 'd'] 
from sklearn.preprocessing import LabelEncoder
# instantiate labelencoder object
le = LabelEncoder()
# apply le on categorical feature columns
data[categorical_cols] = data[categorical_cols].apply(lambda col: le.fit_transform(col))

```

Now I am stuck with how to perform one hot encoding and then join the encoded columns to the dataframe (data). 

Please how do I do this?