remove unused import.
remove unused import.

wikimedia/operations-debs-python-pykafka,sammerry/pykafka,jofusa/pykafka,benauthor/pykafka,thedrow/samsa,aeroevan/pykafka,tempbottle/pykafka,wikimedia/operations-debs-python-pykafka,aeroevan/pykafka,vortec/pykafka,thedrow/samsa,fortime/pykafka,sammerry/pykafka,appsoma/pykafka,yungchin/pykafka,thedrow/samsa,vortec/pykafka,benauthor/pykafka,fortime/pykafka,appsoma/pykafka,jofusa/pykafka,sontek/pykafka,benauthor/pykafka,wikimedia/operations-debs-python-pykafka,sontek/pykafka,yungchin/pykafka,tempbottle/pykafka