def prepare_master_datasets(df: pd.DataFrame, start_date: str = '2021-01-01', end_date:str = None, time_series_split: bool = True, test_start_date: str = '2021-01-01', test_end_date:str = None, test_size: float = 0.2, random_state: int = 42) -> pd.DataFrame:
# function definition
# Funtion call
master_data, X_train_raw, X_test_raw = prepare_master_datasets(claims_data,
start_date='2021-01-01',
end_date='2022-12-31',
time_series_split = True,
test_start_date = '2022-06-30',
test_end_date = '2022-12-31',
test_size=0.2, random_state=SEED)