conditional windows import

IPython/core/magics/script.py

@@ -11,7 +11,6 b' import os'
 import signal
 import sys
 import time
-from asyncio import SafeChildWatcher
 from contextlib import contextmanager
 from subprocess import CalledProcessError
 
@@ -74,6 +73,8 b' def safe_watcher():'
         yield
         return
 
+    from asyncio import SafeChildWatcher
+
     policy = asyncio.get_event_loop_policy()
     old_watcher = policy.get_child_watcher()
     if isinstance(old_watcher, SafeChildWatcher):