...

Host fwi
  Hostname 10.30.30.20
  User django
  Port 22
  Protocol 2
  IdentityFile ~/.ssh/id_idmz
  ProxyCommand  ssh -q -W %h:%p vml030020

Host fw3
  Hostname 10.50.50.250
  User django
  Port 10022
  Protocol 2
  IdentityFile ~/.ssh/id_edmz
  ProxyCommand  ssh -q -W %h:%p fwi

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