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:       I have to go home now , Jenny . Thanks for inviting me to your party . 
 Person2:I'm glad you came . I hope you enjoyed it . 
 Person1:        I had a wonderful time . 

informal