Tests: added ASGI Lifespan.

test/python/lifespan/empty/asgi.py

@@ -0,0 +1,27 @@
+import os
+
+
+async def application(scope, receive, send):
+    if scope['type'] == 'lifespan':
+        with open('version', 'w+') as f:
+            f.write(
+                scope['asgi']['version'] + ' ' + scope['asgi']['spec_version']
+            )
+        while True:
+            message = await receive()
+            if message['type'] == 'lifespan.startup':
+                os.remove('startup')
+                await send({'type': 'lifespan.startup.complete'})
+            elif message['type'] == 'lifespan.shutdown':
+                os.remove('shutdown')
+                await send({'type': 'lifespan.shutdown.complete'})
+                return
+
+    if scope['type'] == 'http':
+        await send(
+            {
+                'type': 'http.response.start',
+                'status': 204,
+                'headers': [(b'content-length', b'0'),],
+            }
+        )