Way to copy a logger's context onto a logger with a different name

I have two loggers, let's say they're named rpc and eval.

I want to handoff processing from the rpc to eval module, but my rpc logger has request info in its context, which I want to include when I make logging calls from the eval logger.

#238 is one solution, I could copy my rpc logger and also name it eval. Alternatively, if there was a way to extract the context from a logger I could either pass that around detached from the original logger, or write a function which adopted the context from a passed-in logger.

Start by reading the existing logger and context APIs, then review issue #238 for the related copy-and-rename approach. Determine how context could be extracted or adopted while changing the logger name; done means a documented, tested way to preserve request context when handing off from rpc to eval.