perl -e "@list=(1..7);$counter=0; foreach $it (@list){if ($counter >= 3){print qq(\n\n);$counter = 0; redo}print qq($it\n); $counter++}"
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##</code><code>##

sub proces_no_more_than_50 {

  my($port,@addresses)=@_;
  if ($#addresses >= 50) {
     &execute( $port, map {shift @addresses} 1..50 );

  }
  else{ &execute($port, @addresses); undef @addresses;}

  &proces_no_more_than_50($port,@addresses) if defined $addresses[0];
}