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Optimized imports, store RPC call result before printing

Co-authored-by: Arun Babu Neelicattu <arun.neelicattu@gmail.com>

Author: theunkn0wn1

README.md

@@ -154,15 +154,17 @@ service Echo {
 
 A client can be implemented as follows:
 ```python
+import asyncio
 import echo
+
 from grpclib.client import Channel
-import asyncio
 
 
 async def main():
     channel = Channel(host="127.0.0.1", port=50051)
     service = echo.EchoStub(channel)
-    print(await service.echo(value="hello", extra_times=1))
+    response = await service.echo(value="hello", extra_times=1)
+    print(response)
 
     async for response in service.echo_stream(value="hello", extra_times=1):
         print(response)