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-rw-r--r--Lib/asyncio/runners.py48
1 files changed, 48 insertions, 0 deletions
diff --git a/Lib/asyncio/runners.py b/Lib/asyncio/runners.py
new file mode 100644
index 0000000..94d9409
--- /dev/null
+++ b/Lib/asyncio/runners.py
@@ -0,0 +1,48 @@
+__all__ = 'run',
+
+from . import coroutines
+from . import events
+
+
+def run(main, *, debug=False):
+ """Run a coroutine.
+
+ This function runs the passed coroutine, taking care of
+ managing the asyncio event loop and finalizing asynchronous
+ generators.
+
+ This function cannot be called when another asyncio event loop is
+ running in the same thread.
+
+ If debug is True, the event loop will be run in debug mode.
+
+ This function always creates a new event loop and closes it at the end.
+ It should be used as a main entry point for asyncio programs, and should
+ ideally only be called once.
+
+ Example:
+
+ async def main():
+ await asyncio.sleep(1)
+ print('hello')
+
+ asyncio.run(main())
+ """
+ if events._get_running_loop() is not None:
+ raise RuntimeError(
+ "asyncio.run() cannot be called from a running event loop")
+
+ if not coroutines.iscoroutine(main):
+ raise ValueError("a coroutine was expected, got {!r}".format(main))
+
+ loop = events.new_event_loop()
+ try:
+ events.set_event_loop(loop)
+ loop.set_debug(debug)
+ return loop.run_until_complete(main)
+ finally:
+ try:
+ loop.run_until_complete(loop.shutdown_asyncgens())
+ finally:
+ events.set_event_loop(None)
+ loop.close()