def convert_to_float(input_string: str) -> Union[float, None]:
    """
    Try to convert a string into float. Return `None` if an error occurs.
    """
    try:
        float_s = float(input_string)
        return float_s
    except:
        return None

    Try to convert a string into float. Return `None` if an error occurs.
    
envs/rstar/eval_src/toolkit_for_MATH/latex_answer_check.py