__START_OF_COMMON_LIB_FILE__
package Class1;
sub new {
    return bless({}, 'Class1');
}

sub method_1 {
    print "I'm method 1!\n";
}

package Class2;
sub new {
    return bless({}, 'Class2');
}

sub method_2 {
    print "I'm method 2!\n";
}

1;
__END_OF_COMMON_LIB_FILE__