Minor Travis fix for py3 build.
Minor Travis fix for py3 build.

pycontribs/jira,dbaxa/jira,pycontribs/jira,m42e/jira,akosiaris/jira,kinow/jira,rayyen/jira,kinow/jira,akosiaris/jira,m42e/jira,milo-minderbinder/jira,stevencarey/jira,dbaxa/jira,rayyen/jira,dwmarshall/pycontribs-jira,dwmarshall/pycontribs-jira,coddingtonbear/jira,coddingtonbear/jira,milo-minderbinder/jira,awurster/jira,stevencarey/jira,awurster/jira,VikingDen/jira,VikingDen/jira