Autocompletion in the language selector normally continues the text written by the user. However, in some cases such as ISO codes, the input from the user is not a prefix of the autocompletion text (e.g., the user types "pt" for "portuguese"). In such cases angle brackets are used, as shown below:

Angle brackets don't look very natural in this context, and parenthesis cannot be used since some languages already use them in their name.
Instead of angle brackets we can use an em dash (—) as a separator for the suggestion instead.
It reads more naturally and looks less like software code, as illustrated below.