/usr/share/tripleo-image-elements/network-utils/README.md is in python-tripleo-image-elements 0.7.1-1.
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| 1 2 3 4 5 6 7 8 9 10 11 12 | Install a set of network utility scripts
Currently only installs a single script
ensure-bridge : A bridge configuration script which can be used to create
  a ovs bridge and place a network device on it. Transferring ip addresses and
  routes to the bridge. The script takes 3 parameters
  $ ensure-bridge EXTERNAL_BRIDGE PHYSICAL_INTERFACE [PUBLIC_INTERFACE_ROUTE]
  EXTERNAL_BRIDGE        : The name of the bridge to create.
  PHYSICAL_INTERFACE     : The physical interface to place on the bridge.
  PUBLIC_INTERFACE_ROUTE : Add a default route via this for all IP's except
                           169.254.169.254/32
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