import json


def _is_json(str_to_check: str) -> bool:
    """
    Checks if str is JSON

    :param str_to_check: sting to check

    :return: true if str is JSON, otherwise raises ValueError or TypeError

    :raises TypeError: if str_to_check is not str type
    :raises ValueError: if str_to_check is not valid JSON
    """
    json.loads(str_to_check)
    return True