fix test

Author: xuantengh

Lib/test/test_monitoring.py

@@ -3,6 +3,7 @@
 import collections
 import dis
 import functools
+import inspect
 import math
 import operator
 import sys
@@ -1717,10 +1718,13 @@ def func(s: str) -> int:
                 return 0
 
         def callback(code, from_, to):
-            frame = sys._getframe(0)
-            old = frame.f_lineno
             # try set frame.f_lineno
-            frame.f_lineno = frame.f_lineno
+            frame = inspect.currentframe()
+            while frame and frame.f_code is not code:
+                frame = frame.f_back
+
+            self.assertIsNotNone(frame)
+            frame.f_lineno = frame.f_lineno + 1 # run next instruction
 
         sys.monitoring.set_local_events(TEST_TOOL, func.__code__, E.BRANCH_LEFT)
         sys.monitoring.register_callback(TEST_TOOL, E.BRANCH_LEFT, callback)