@classmethod
def _from_dict(cls, _dict):
    """Initialize a Class object from a json dictionary."""
    args = {}
    if 'class' in _dict or 'class_name' in _dict:
        args['class_name'] = _dict.get('class') or _dict.get('class_name')
    else:
        raise ValueError("Required property 'class' not present in Class JSON")
    return cls(**args)
