swap import order of lxml
swap import order of lxml

lxml is a third party library, so attempt to import it with six rather
than first, which makes it look like a package from stdlib.

Change-Id: I43028d326f17ea8cd0aaf7a3b80bf291d2bf0982

blueboxgroup/keystone,himanshu-setia/keystone,vivekdhayaal/keystone,takeshineshiro/keystone,jamielennox/keystone,ajayaa/keystone,rushiagr/keystone,UTSA-ICS/keystone-kerberos,mahak/keystone,maestro-hybrid-cloud/keystone,roopali8/keystone,rushiagr/keystone,nuxeh/keystone,dims/keystone,roopali8/keystone,ilay09/keystone,jumpstarter-io/keystone,promptworks/keystone,openstack/keystone,klmitch/keystone,vivekdhayaal/keystone,dstanek/keystone,MaheshIBM/keystone,mahak/keystone,UTSA-ICS/keystone-kerberos,ging/keystone,klmitch/keystone,ilay09/keystone,promptworks/keystone,dstanek/keystone,mahak/keystone,takeshineshiro/keystone,cernops/keystone,rajalokan/keystone,openstack/keystone,idjaw/keystone,jonnary/keystone,jumpstarter-io/keystone,rushiagr/keystone,openstack/keystone,himanshu-setia/keystone,cernops/keystone,ilay09/keystone,jonnary/keystone,maestro-hybrid-cloud/keystone,nuxeh/keystone,promptworks/keystone,jamielennox/keystone,MaheshIBM/keystone,rajalokan/keystone,nuxeh/keystone,dims/keystone,rodrigods/keystone,rajalokan/keystone,ajayaa/keystone,rodrigods/keystone,vivekdhayaal/keystone,idjaw/keystone,blueboxgroup/keystone,jumpstarter-io/keystone,ging/keystone,dstanek/keystone