CODE EXAMPLE FOR PYTHON

traint test split on column id

splitter = GroupShuffleSplit(test_size=.20, n_splits=2, random_state = 7)
split = splitter.split(df, groups=df['Group_Id'])
train_inds, test_inds = next(split)

train = df.iloc[train_inds]
test = df.iloc[test_inds]