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 shall I call him ?  
 Person2:Oh , you may call him Uncle , or Henry .  
 Person1:        What's he doing ?  
 Person2:He's checking bags.He ' s an official in the customs . 

formal