Add providers async injections example

docs/providers/async.rst

@@ -10,3 +10,8 @@ Asynchronous injections
                  demonstrates how make asynchronous dependency injections in Python.
 
 Providers support asynchronous injections.
+
+.. literalinclude:: ../../examples/providers/async.py
+   :language: python
+   :emphasize-lines: 26-29
+   :lines: 3-

examples/providers/async.py

@@ -0,0 +1,37 @@
+"""Asynchronous injections example."""
+
+import asyncio
+
+from dependency_injector import containers, providers
+
+
+async def init_async_resource():
+    await asyncio.sleep(0.1)
+    yield 'Initialized'
+
+
+class Service:
+    def __init__(self, resource):
+        self.resource = resource
+
+
+class Container(containers.DeclarativeContainer):
+
+    resource = providers.Resource(init_async_resource)
+
+    service = providers.Factory(
+        Service,
+        resource=resource,
+    )
+
+
+async def main(container: Container):
+    resource = await container.resource()
+    service = await container.service()
+    ...
+
+
+if __name__ == '__main__':
+    container = Container()
+
+    asyncio.run(main(container))