bpo-36064: Clarify allowed data types for urllib.request.Request. (GH-11990)
diff --git a/Doc/library/urllib.request.rst b/Doc/library/urllib.request.rst
index 289bfca..f56da1b 100644
--- a/Doc/library/urllib.request.rst
+++ b/Doc/library/urllib.request.rst
@@ -192,8 +192,8 @@
*data* must be an object specifying additional data to send to the
server, or ``None`` if no such data is needed. Currently HTTP
requests are the only ones that use *data*. The supported object
- types include bytes, file-like objects, and iterables. If no
- ``Content-Length`` nor ``Transfer-Encoding`` header field
+ types include bytes, file-like objects, and iterables of bytes-like objects.
+ If no ``Content-Length`` nor ``Transfer-Encoding`` header field
has been provided, :class:`HTTPHandler` will set these headers according
to the type of *data*. ``Content-Length`` will be used to send
bytes objects, while ``Transfer-Encoding: chunked`` as specified in