I'm not sure whether you want your foo line or not.
But this will do for small sets.

#!/usr/bin/perl
use strict;
use warnings;

foreach (<DATA>) {
        if ( /begin/ .. /end/) {
            if ( /begin/ ) {
                print "You want to skip me, yes? $_";
                next;
            }
            print;
            next;
        }
}
__END__
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begin
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end
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