def METHOD_NAME(text: str, case: str = "upper") -> str:
    if case == "upper":
        text_new = text.upper()
    elif case == "lower":
        text_new = text.lower()
    elif case == "mixed":  # keep as-is, mix-cases
        text_new = text
    else:
        raise ValueError(f"Case <{case}> is not supported. Please specify either 'upper', 'lower', or 'mixed'.")
    return text_new