# HG changeset patch
# User Ilya Etingof <etingof@gmail.com>
# Date 1569913490 -7200
#      Tue Oct 01 09:04:50 2019 +0200
# Node ID c7a8a8d8f738e8a29b8ef1020e6a79c6192ac890
# Parent  c9ce5f43660a9455c6e56475665e28c6b01c2bd9
Update docstring on streaming.read

Co-Authored-By: Jan Pipek <jan.pipek@gmail.com>

diff --git a/pyasn1/codec/streaming.py b/pyasn1/codec/streaming.py
--- a/pyasn1/codec/streaming.py
+++ b/pyasn1/codec/streaming.py
@@ -209,7 +209,7 @@
 
     Yields
     ------
-    : :py:class:`bytes` or :py:class:`str` or None
+    : :py:class:`bytes` or :py:class:`str` or :py:class:`SubstrateUnderrunError`
         Returns read data or :py:class:`~pyasn1.error.SubstrateUnderrunError`
         object if no `size` bytes is readily available in the stream. The
         data type depends on Python major version