If the module 'Module' is already loaded, then the declaration

use autouse 'Module' => qw(func1 func2($;$));

is equivalent to

use Module qw(func1 func2);

If the module Module is not loaded yet, then the above declaration
declares functions func1() and func2() in the current package. When
these functions are called, they load the package Module if needed, and
substitute themselves with the correct definitions.