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:       If I remember correctly , time of delivery is another point in which we differ . 
 Person2:That's right . Let's go into details of it . 
 Person1:        Ok . I hope you can have these goods delivered before the end of September . We'd like them to be ready in time for our Christmas sales . 
 Person2:Christmas doesn't come until the end of the year , does it ? 
 Person1:        No . But in the United States , the Christmas season begins about a month before December 25 . 
 Person2:Well , I'm afraid a little bit difficult for us to advanced the time of shipment . Our manufacturers are fully committed at the moment . 
 Person1:        I hope you can try to get them to step up production . 
 Person2:They are already working three shifts a day to step up production as new orders keep pouring in . 
 Person1:        If that's the case , there's nothing to be done about it . 
 Person2:I'm sorry . 
 Person1:        What's your last word as to the delivery date then ? 
 Person2:By the middle of October . This is the best we can do . 
 Person1:        All right . I'll take your words at that . 
 Person2:Good . Let's call it a deal . And we'll do our best to advance the shipment , but your letter of credit should be opened early September . 
 Person1:        I promise . 

formal