| #!/bin/bashset -utrap '[ ${#PIDS[@]} -gt 0 ] && kill -TERM ${PIDS[@]}' TERMdeclare -a PIDSfor port in $WEB_PORTS; do	echo starting a web server listening on port $port;	/webserver.py $port &	PIDS+=($!)donewait ${PIDS[@]}trap - TERMwait ${PIDS[@]}
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