def check_missing_values(df): ...
def check_data_types(df): ...
def check_datetime_order(df): ...
def check_price_reasonableness(df): ...
def check_volume_amount(df): ...
def check_symbol_consistency(df): ...
def check_duplicate_records(df): ...
def check_extreme_values(df, threshold: float = 0.2): ...
def check_kline_quality(df): ...
