libcontext-preserve-perl binary package in Ubuntu Focal amd64

 Context::Preserve allows developers to preserve the calling context of their
 subroutines, which is useful for functions that call other functions and
 return their results, with some possible modifications. This means that, if
 your module is called in scalar, list or void context, the given subroutine
 is called in the same context and the appropriate 'thing' is returned.
 .
 This means that it is easy to write functions that call other functions,
 modify their result and return it, in a seamless manner.

Source package