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:       What is that you have there ?  
 Person2:Aah ! Close your eyes . You aren't supposed to see this .  
 Person1:        Ah ha ! I caught you . Just let me peek . I won't tell anyone .  
 Person2:You can't peek ! This is a surprise .  
 Person1:        How about one little hint ?  
 Person2:Here's one little hint . If you don't go out right now , this won't be under the tree .  
 Person1:        That's a very good hint .  
 Person2:And please shut the door and lock it behind you ! 

formal