Definition: You are given a conversation between two people. 'Person1:' and 'Person2:' are used to separate their respective dialogues. You are required to assign a label 'formal' if there is an absence of emotion and a presence of questions anywhere within the conversation. If such pattern is not found assign the label 'informal'.
Input:  Person1:       When do you plan to deliver the goods ?  
 Person2:This weekend .  
 Person1:        Please pay close attention to the safety of the shipment .  
 Person2:Don't worry about that.We have experience . 

formal