added solution of tutorial 7

goodchain/src/classes/TxBlock.py

@@ -36,6 +36,10 @@ class TxBlock (CBlock):
         for tx in self.data:
             if not tx.is_valid():
                 return False
+            
+        if self.nonce != "A random nonce":
+            if not self.good_nonce():
+                return False
         
         total_in, total_out = self.__count_totals()