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:       Hello . Manchester 6739792 .  
 Person2:Hello . Is that Nicholas ?  
 Person1:        Nicholas ? Nicholas Nickleby ? No . He doesn't live here any more . He's moved to Morecambe .  
 Person2:Never ! Do you know his new number ?  
 Person1:        Yes . I've got it somewhere . Let me see . Where did I put it ? Ah - I remember , it's on the memo . Here it is . Do you have a pen to write it down ?  
 Person2:Yes , I do . Go on .  
 Person1:        His number's 4945939 .  
 Person2:4945939 . Marvellous ! Thanks for your help . 

informal