fix compatibility issue with rest_framework 3.3.3
fix compatibility issue with rest_framework 3.3.3

jermowery/xos,cboling/xos,cboling/xos,xmaruto/mcord,jermowery/xos,jermowery/xos,xmaruto/mcord,jermowery/xos,cboling/xos,xmaruto/mcord,cboling/xos,cboling/xos,xmaruto/mcord