return commit_ts in the function 'commit()' in txn.py (#213)

* return commit_ts in the function 'commit()' in txn.py

Author: seedoilz

examples/simple/simple.py

@@ -78,7 +78,8 @@ def create_data(client):
         response = txn.mutate(set_obj=p)
 
         # Commit transaction.
-        txn.commit()
+        commit_response = txn.commit()
+        print(commit_response)
 
         # Get uid of the outermost object (person named "Alice").
         # response.uids returns a map from blank node names to uids.
@@ -106,7 +107,8 @@ def delete_data(client):
             print("Bob's UID: " + person['uid'])
             txn.mutate(del_obj=person)
             print('Bob deleted')
-        txn.commit()
+        commit_response = txn.commit()
+        print(commit_response)
 
     finally:
         txn.discard()

pydgraph/txn.py

@@ -235,7 +235,7 @@ def commit(self, timeout=None, metadata=None, credentials=None):
 
         new_metadata = self._dg.add_login_metadata(metadata)
         try:
-            self._dc.commit_or_abort(self._ctx, timeout=timeout,
+            return self._dc.commit_or_abort(self._ctx, timeout=timeout,
                                      metadata=new_metadata,
                                      credentials=credentials)
         except Exception as error: