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 , what's up ?  
 Person2:Nothing really .  
 Person1:        I'm throwing a party on Friday .  
 Person2:I didn't realize that .  
 Person1:        You didn't ?  
 Person2:Nobody has told me anything about your party .  
 Person1:        Did you want to go ?  
 Person2:When does it start ?  
 Person1:        At 8  
 Person2:I'll be there .  
 Person1:        I'd better see you there .  
 Person2:Of course . 

formal