The Gitlab documentation allows to introduce sections into the CODEOWNERS such as

[README Owners]
README.md @user1 @user2
internal/README.md @user2

That enables Gitlab to show the code ownership within the UI a little bit nicer. Currently, running this tool (version 1.1.1) on such a file leads to the following error:

$ codeowners
line 1: unexpected character '[' at position 1

Would you be willing to allow support for this? Would you accept a PR for that (I haven't looked into the code yet though)