push me in the AM

hail/python/hailtop/__init__.py

@@ -27,34 +27,20 @@ def is_notebook() -> bool:
     return IS_NOTEBOOK
 
 
-_hail_created_the_main_thread_event_loop = False
-
-
 def hail_event_loop():
-    '''If an event loop exists and Hail did not create it, use nest_asyncio to allow Hail's event
-    loops to nest inside it.
-
-    If an event loop exists and Hail did create it, then a developer is trying to use async inside
-    sync inside async. That is forbidden.
+    '''If a running event loop exists, use nest_asyncio to allow Hail's event loops to nest inside
+    it.
 
     If no event loop exists, ask asyncio to get one for us.
 
     '''
-    global _hail_created_the_main_thread_event_loop
-
     import asyncio  # pylint: disable=import-outside-toplevel
     import nest_asyncio  # pylint: disable=import-outside-toplevel
 
     try:
         asyncio.get_running_loop()
 
-        if _hail_created_the_main_thread_event_loop:
-            raise ValueError(
-                'As a matter of Hail team policy, you are not allowed to nest asynchronous Hail code '
-                'inside synchronous Hail code.'
-            )
-
         nest_asyncio.apply()
         return asyncio.get_running_loop()
-    except RuntimeError as err:
+    except RuntimeError:
         return asyncio.get_event_loop()

hail/python/hailtop/fs/fs_utils.py

@@ -12,7 +12,7 @@
 
 def _fs() -> RouterFS:
     '''Return an FS for this particular thread.'''
-    global _router_fs
+    global _router_fs_for_loop
 
     loop = hail_event_loop()
     if fs := _router_fs_for_loop.get(loop):

hail/python/hailtop/httpx.py

@@ -93,7 +93,7 @@ def __init__(self,
                  **kwargs):
         try:
             self.loop_at_creation_time = asyncio.get_running_loop()
-        except RuntimeError as err:
+        except RuntimeError:
             raise ValueError(
                 'aiohttp.ClientSession stashes a copy of the event loop into a field. Very confusing '
                 'errors arise if that stashed event loop differs from the currently running one. '