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:       Nice day today , isn't it ?  
 Person2:Yes , it's beautiful weather we're having .  
 Person1:        We can't complain about the weather recently .  
 Person2:Yes , the sun shines day after day . It's neither too hot nor too cold .  
 Person1:        I wonder how long this weather can last .  
 Person2:I hope it will stay fine tomorrow . I'm going to have a picnic with my family . 

informal