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:       Where is your native place ?  
 Person2:My native place is Shanghai , which is a very beautiful cosmopolitan city .  
 Person1:        So are you a local ?  
 Person2:Yes , I am a local resident . 

formal