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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def getexif_location(directory,fn):
 """ directory - Dir where file is located fn - filename to check for EXIF GPS Returns touple of lat,lon if EXIF eg. (34.035460,-118.227885) files contains GPS info, otherwise returns None,None """

    lat=None
    lon=None

    sign_lat=+1.0
    sign_lon=+1.0
    # Check if photo as geo info already
    exif_tags=exifread.process_file(\
            open(os.path.join(directory,fn),'rb'))
    try:
        d,m,s=exif_tags['GPS GPSLongitude'].values
        # West is negative longitudes, change sign
        if exif_tags['GPS GPSLongitudeRef'].values=='W':
            sign_lon=-1.0
        lon=float(d.num) +float(m.num)/60.0 +float(s.num/float(s.den))/3600.0
        lon=lon*sign_lon
        d,m,s=exif_tags['GPS GPSLatitude'].values
        # South is negative latitude, change sign
        if exif_tags['GPS GPSLatitudeRef'].values=='S':
            sign_lat=-1.0
        lat=float(d.num)\
                +float(m.num)/60.0\
                +float(s.num/float(s.den))/3600.0
        lat=lat*sign_lat
    except:
        logger.debug("%s - Couldn't extract GPS info"%(fn))

    return lat,lon