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:       Hey . I'm a visitor from China . I love your music . It's the best I've ever heard . Will you please spare a little bit of time for me ?  
 Person2:Sure . Thank you for saying that . Actually , those songs were sung for the first time today . I wrote them in the past two months .  
 Person1:        Oh , you wrote them all by yourself . That's amazing ! Are you a regular singer here ?  
 Person2:You can say that . But my band and I also sing regularly in several other places , too .  
 Person1:        Cool . Your guitar skills are very impressive . How did you learn to play like that ?  
 Person2:I picked up guitar at an early age , maybe around 8 years old . Afterward , I taught myself by listening to some records of top players .  
 Person1:        Wow , that's unbelievable ! You play so well , but you've never been to a real teacher . You will definitely be famous in the near future . 

informal