--- dev.pl
	#!/usr/bin/perl -w
	use strict;
	use lib './';
	use MyPackage;
	
	
	--- MyPackage.pm
	package MyBase;
	use strict;
	use Utils;

	# return true
	1;
	
	
	--- Utils.pm
	package MyPackage;
	use strict;

	# export
	use base 'Exporter';
	our @EXPORT = qw{mysub};

	# import
	sub import {
		# what goes here to set $var in the caller package?
		# E.g. $MyPackage::var
		
		# export symbols
		MyPackage->export_to_level(1, @_);
	}

	# some subroutine
	sub mysub {
		# how do I access $var in the caller package?
		# E.g. $MyPackage::var
	}

	# return true
	1;