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:       How about going to hear a country-and-western singer tonight ?  
 Person2:I'd enjoy that .  
 Person1:        I'll pick you up around 8: 00 .  
 Person2:OK . I'll see you then . 

informal