Any method for updating User Fields in an exiting Document?

[pandas-a11y-11]

Due to lack of documentation or examples, it is hard to figure out whether odfdo provides a way to a) locating elements in an existing tree (e.g. a user field), b) any way of filling those fields in an existing document. Please, help.

[pandas-a11y-11]

I figured it out, it seems, but I'd still ask to add an example with user fields, please. Similar libraries, e.g. odfpy, ezodf cover this issue, but the syntax and structure used here makes it hard to decipher the steps without a guide within reasonable time for such a trivial task.