Adding groupby aggregate features with featurewiz

fw_add_groupby_agg_features.py

### create groupby aggregates of the following numerics 
agg_nums = ['cont1','cont3']
groupby_vars = ['cat2','cat4']
train_add, test_add = FW.FE_add_groupby_features_aggregated_to_dataframe(train[agg_nums+groupby_vars], 
                                agg_types=['mean','std'],
                                groupby_columns=groupby_vars,
                                ignore_variables=[] , test=test[agg_nums+groupby_vars])

# join the dataframes with the aggregated features to the main training and testing set dataframes
train_copy = train.join(train_add.drop(groupby_vars+agg_nums, axis=1))
test_copy = test.join(test_add.drop(groupby_vars+agg_nums, axis=1))