Using pike magnum with ocata for the rest

user_variables.yml

# The py_pkgs lookup will ignore all _git_ variables unless the
# _git_repo variable is present. As we're not wanting to use a
# fork in this case we just have the default value here.
magnum_git_repo: https://git.openstack.org/openstack/magnum

# Now we set the SHA/branch we want to build magnum from.
magnum_git_install_branch: "stable/pike"

# The key change is to allow the build to happen with the
# upstream indexes enabled (which is disabled by default to
# lock down where the packages come from). By applying this
# setting we're opening up the wheel build to use more than
# what is available on the repo server.
magnum_git_install_fragments: "venvwithindex=True"