Docs: Update smart_open example code to prevent decompression error (f…

…ixes #59). (#60)

README.md

@@ -203,15 +203,21 @@ session = boto3.Session(
 
 url = 's3://clp-example-s3-bucket/example.clp.zst'
 # Using `smart_open.open` to stream the encoded CLP IR:
-with smart_open.open(url, "rb", transport_params={'client': session.client('s3')}) as istream:
+with smart_open.open(
+    url, mode="rb", compression="disable", transport_params={"client": session.client("s3")}
+) as istream:
     with ClpIrStreamReader(istream, allow_incomplete_stream=True) as clp_reader:
         for log_event in clp_reader:
             # Print the log message with its timestamp properly formatted.
             print(log_event.get_formatted_message())
 ```
 
 Note:
-When `allow_incomplete_stream` is set to False (default), the reader will raise
+- Setting `compression="disable"` is necessary so that `smart_open` doesn't
+undo the IR file's Zstandard compression (based on the file's extension) before
+streaming it to `ClpIrStreamReader`; `ClpIrStreamReader` expects the input
+stream to be Zstandard-compressed.
+- When `allow_incomplete_stream` is set to False (default), the reader will raise
 `clp_ffi_py.ir.IncompleteStreamError` if the stream is incomplete (it doesn't end
 with the byte sequence indicating the stream's end). In practice, this can occur
 if you're reading a stream that is still being written or wasn't properly