public bool CanAnswerQuestion(Question question)
 {
     return question.Contains(DateOrTimeToken) && question.ContainsExactNumberOfMatches(CityOrTimezoneToken, 2); ;
 }
 public bool CanAnswerQuestion(Question question)
 {
     return (question.Contains(LiteralDateOrTime) && question.ContainsExactNumberOfMatches(CityOrTimezoneToken, 1)) || (question.Contains(Timezone) && question.Tokens.Count == 1);
 }