docs/uerrno: Fix xref-vs-code markup.
@@ -17,7 +17,7 @@ Constants
Error codes, based on ANSI C/POSIX standard. All error codes start with
"E". As mentioned above, inventory of the codes depends on
`MicroPython port`. Errors are usually accessible as ``exc.args[0]``
- where `exc` is an instance of `OSError`. Usage example::
+ where ``exc`` is an instance of `OSError`. Usage example::
try:
uos.mkdir("my_dir")
