@staticmethod
def get_private_attr_name(class_name):
    """Helper method to prepend a leading underscore to a provided class name.

        :param class_name: Name of a class under this category.
        :type class_name: str|unicode
        :return: The private attribute label for the provided class.
        :rtype: str
        """
    private_attr_name = '_{class_name}'.format(class_name=class_name)
    return private_attr_name
