code: func (r *EchoRequest) VerifyTimestamp() bool {
  	reqTimestamp, _ := time.Parse("2006-01-02T15:04:05Z", r.Request.Timestamp)
  	if time.Since(reqTimestamp) < time.Duration(150)*time.Second {
  		return true
  	}
  
  	return false
  }
docs: // Request Functions
  // VerifyTimestamp will parse the timestamp in the EchoRequest and verify that it is in the correct
  // format and is not too old. True will be returned if the timestamp is valid; false otherwise.