@staticmethod
def get_class_data_type_key(class_name: str) ->str:
    """Builds class key string based on capital letters of class name i.e. for 'FooBarClass' would return 'fbc'.
        """
    data_type_key = ''
    for letter in class_name:
        if 'A' <= letter <= 'Z':
            data_type_key += letter
    return data_type_key.lower()
