def lookupfile(filename):
logger.info('<STR_LIT>'%(filename))<EOL>dirname=os.path.dirname(filename)<EOL>basefilename=os.path.basename(filename)<EOL>CACHE_FILE = os.path.join(dirname,'<STR_LIT:.>'+basefilename+'<STR_LIT>')<EOL>cache=loadCacheFile(CACHE_FILE)<EOL>positions=parsePositionFile(filename)<EOL>if not cache:<EOL><INDENT>logger.info("<STR_LIT>"%(basefilename))<EOL>cache=lookupGeoInfo(positions)<EOL>json.dump(cache,open(CACHE_FILE,'<STR_LIT:w>'))<EOL><DEDENT>else:<EOL><INDENT>logger.info("<STR_LIT>"%(basefilename))<EOL><DEDENT>return positions,cache<EOL>
Returns dictionary of file content as well 
    as google reverse GEO data