@staticmethod
def merge_list_no_duplicates(a1, a2):
    """
        merge two lists by overwriting the original with the second one if the key exists
        :param a1:
        :param a2:
        :return:
        """
    r = []
    if isinstance(a1, list) and isinstance(a2, list):
        r = a1
        for i in a2:
            if i not in a1:
                r.append(i)
    return r
