feat: completed solutions

exercises/07_structs/structs3.rs

@@ -24,14 +24,16 @@ impl Package {
     }
 
     // TODO: Add the correct return type to the function signature.
-    fn is_international(&self) {
+    fn is_international(&self) -> bool {
         // TODO: Read the tests that use this method to find out when a package
         // is considered international.
+        self.sender_country != self.recipient_country
     }
 
     // TODO: Add the correct return type to the function signature.
-    fn get_fees(&self, cents_per_gram: u32) {
+    fn get_fees(&self, cents_per_gram: u32) -> u32 {
         // TODO: Calculate the package's fees.
+        cents_per_gram * self.weight_in_grams
     }
 }