How do I correct an ambiguous reference in a library?

I have 2 libraries which both implement 'File'

I also have a third library which references File, and therefore causes the standard error "reference to X is ambiguous"

I understand the problem, and that I can usually prefix the reference with its class like this in my code: CorrectLib::File

What is the correct way to handle this when the offending code is IN another library?
Should i just go hack the library and stick the full reference in there?

What happens when the library gets updated or someone installs the vanilla library, is there a way to provide a hint in the code to get the library to reference the correct 'File'?