fix deprecation warning
fix deprecation warning

KeyproOy/OWSLib,b-cube/OWSLib,geopython/OWSLib,ocefpaf/OWSLib,menegon/OWSLib,dblodgett-usgs/OWSLib,Jenselme/OWSLib,gfusca/OWSLib,bird-house/OWSLib,jachym/OWSLib,daf/OWSLib,jaygoldfinch/OWSLib,datagovuk/OWSLib,QuLogic/OWSLib,robmcmullen/OWSLib,geographika/OWSLib,kalxas/OWSLib,JuergenWeichand/OWSLib,jaygoldfinch/OWSLib,daf/OWSLib,datagovuk/OWSLib,kwilcox/OWSLib,daf/OWSLib,datagovuk/OWSLib,mbertrand/OWSLib,tomkralidis/OWSLib