Selecting a random member of a bash array

I came across this little tidbit today, I wish I hadn't closed my browser so I could give adequate credit but here is how to select a random port out of an array of ports in bash:

DEST_PORTS=(22229 31457 42853)
function pickDestPort ()
{
  RANDOM=$$$(date +%s)
  selectedport=${DEST_PORTS[$RANDOM % ${#DEST_PORTS[@]} ]}
  echo $selectedport
}

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