use xxx;    #imports all of the symbols in @EXPORT
use xxx (); #imports none of the symbols in @EXPORT
            #this empty list is the same as:  (updated)
            #BEGIN { require Module }
use xxx qw(OpenConnection $LoggedOn_user_id); # imports
 # all of the symbols in @EXPORT AND subroutine OpenConnection
 # AND the scalar $LoggedOn_user_id from @EXPORT_OK