@staticmethod
def safe_string(dictionary, key, default_value=None):
    return (str(dictionary[key]) if ((key is not None) and (key in dictionary) and (dictionary[key] is not None)) else default_value)
@staticmethod
def safe_string(dictionary, key, default_value=None):
    return (str(dictionary[key]) if ((key is not None) and (key in dictionary) and (dictionary[key] is not None)) else default_value)