anchor.diff:    }
   
     static Map _toMap(PostalAddress address) => {
  -        "label": address.label,
  -        "street": address.street,
  -        "city": address.city,
  -        "postcode": address.postcode,
  -        "region": address.region,
  -        "country": address.country
  -      };
  +    "label": address.label,
  +    "street": address.street,
  +    "city": address.city,
  +    "postcode": address.postcode,
  +    "region": address.region,
  +    "country": address.country
  +  };
   }
   
   /// Item class used for contact fields which only have a [label] and
  
positive.code: }
  
  class Contact {
    Contact(
        {this.givenName,
        this.middleName,
        this.prefix,
        this.suffix,
        this.familyName,
        this.company,
        this.jobTitle,
        this.emails,
        this.phones,
        this.postalAddresses,
        this.avatar});
  
    String identifier,
        displayName,
        givenName,
        middleName,
        prefix,
        suffix,
        familyName,
        company,
        jobTitle;
    Iterable<Item> emails = [];
    Iterable<Item> phones = [];
    Iterable<PostalAddress> postalAddresses = [];
  
negative.code: }
  
  class PostalAddress {
    PostalAddress({
      this.label,
      this.street,
      this.city,
      this.postcode,
      this.region,
      this.country
    });
    String label, street, city, postcode, region, country;
  
    PostalAddress.fromMap(Map m) {
  