Update app.py

app.py

@@ -344,7 +344,7 @@ def merge_trans():
             'balance': previous_post_send['balance'], 
             'proof': previous_post_send['proof'],
             'previous_hash': previous_post_send['previous_hash'],
-            'block': blockchain.print_previous_block()['index']+1}
+            'block': len(blockchain.chain)}
     rec_block = {
             'role': 'Recipient',
             'name': previous_post_rec['transactions'][0]['recipient'],
@@ -355,7 +355,7 @@ def merge_trans():
             'balance': previous_post_rec['balance'], 
             'proof': previous_post_rec['proof'],
             'previous_hash': previous_post_rec['previous_hash'],
-            'block': blockchain.print_previous_block()['index']+1}
+            'block': len(blockchain.chain)}
 
     trans_bx.append(send_block)
     trans_bx.append(rec_block)