Fix PEP8 in openspending/tasks.
Fix PEP8 in openspending/tasks.

johnjohndoe/spendb,nathanhilbert/FPA_Core,nathanhilbert/FPA_Core,spendb/spendb,openspending/spendb,CivicVision/datahub,USStateDept/FPA_Core,CivicVision/datahub,openspending/spendb,pudo/spendb,pudo/spendb,spendb/spendb,USStateDept/FPA_Core,CivicVision/datahub,pudo/spendb,nathanhilbert/FPA_Core,spendb/spendb,USStateDept/FPA_Core,openspending/spendb,johnjohndoe/spendb,johnjohndoe/spendb