avoid internal use of deprecated asyncio.iscoroutinefunction

Lib/asyncio/base_events.py

@@ -18,6 +18,7 @@
 import concurrent.futures
 import functools
 import heapq
+import inspect
 import itertools
 import os
 import socket
@@ -766,7 +767,7 @@ def call_soon(self, callback, *args, context=None):
 
     def _check_callback(self, callback, method):
         if (coroutines.iscoroutine(callback) or
-                coroutines.iscoroutinefunction(callback)):
+                inspect.iscoroutinefunction(callback)):
             raise TypeError(
                 f"coroutines cannot be used with {method}()")
         if not callable(callback):

Lib/asyncio/unix_events.py

@@ -2,6 +2,7 @@
 
 import errno
 import io
+import inspect
 import itertools
 import os
 import selectors
@@ -92,7 +93,7 @@ def add_signal_handler(self, sig, callback, *args):
         Raise RuntimeError if there is a problem setting up the handler.
         """
         if (coroutines.iscoroutine(callback) or
-                coroutines.iscoroutinefunction(callback)):
+                inspect.iscoroutinefunction(callback)):
             raise TypeError("coroutines cannot be used "
                             "with add_signal_handler()")
         self._check_signal(sig)

Lib/unittest/mock.py

@@ -31,7 +31,7 @@
 import sys
 import builtins
 import pkgutil
-from asyncio import iscoroutinefunction
+from inspect import iscoroutinefunction
 from types import CodeType, ModuleType, MethodType
 from unittest.util import safe_repr
 from functools import wraps, partial