fix(client): correctly flush the stream response body (#230)

src/anthropic/_streaming.py

@@ -45,8 +45,9 @@ def __stream__(self) -> Iterator[ResponseT]:
         cast_to = self._cast_to
         response = self.response
         process_data = self._client._process_response_data
+        iterator = self._iter_events()
 
-        for sse in self._iter_events():
+        for sse in iterator:
             if sse.event == "completion":
                 yield process_data(data=sse.json(), cast_to=cast_to, response=response)
 
@@ -68,6 +69,10 @@ def __stream__(self) -> Iterator[ResponseT]:
                     response=self.response,
                 )
 
+        # Ensure the entire stream is consumed
+        for sse in iterator:
+            ...
+
 
 class AsyncStream(Generic[ResponseT]):
     """Provides the core interface to iterate over an asynchronous stream response."""
@@ -102,8 +107,9 @@ async def __stream__(self) -> AsyncIterator[ResponseT]:
         cast_to = self._cast_to
         response = self.response
         process_data = self._client._process_response_data
+        iterator = self._iter_events()
 
-        async for sse in self._iter_events():
+        async for sse in iterator:
             if sse.event == "completion":
                 yield process_data(data=sse.json(), cast_to=cast_to, response=response)
 
@@ -125,6 +131,10 @@ async def __stream__(self) -> AsyncIterator[ResponseT]:
                     response=self.response,
                 )
 
+        # Ensure the entire stream is consumed
+        async for sse in iterator:
+            ...
+
 
 class ServerSentEvent:
     def __init__(