@classmethod
def _from_dict(cls, _dict):
    """Initialize a MessageContextGlobalSystem object from a json dictionary."""
    args = {}
    if 'timezone' in _dict:
        args['timezone'] = _dict.get('timezone')
    if 'user_id' in _dict:
        args['user_id'] = _dict.get('user_id')
    if 'turn_count' in _dict:
        args['turn_count'] = _dict.get('turn_count')
    return cls(**args)
