Fixed pyflakes errors for .checks imports
Fixed pyflakes errors for .checks imports

readevalprint/mezzanine,frankier/mezzanine,dsanders11/mezzanine,wbtuomela/mezzanine,frankier/mezzanine,ryneeverett/mezzanine,frankier/mezzanine,molokov/mezzanine,stephenmcd/mezzanine,readevalprint/mezzanine,stephenmcd/mezzanine,wbtuomela/mezzanine,jerivas/mezzanine,wbtuomela/mezzanine,christianwgd/mezzanine,readevalprint/mezzanine,ryneeverett/mezzanine,jerivas/mezzanine,christianwgd/mezzanine,dsanders11/mezzanine,christianwgd/mezzanine,molokov/mezzanine,jerivas/mezzanine,dsanders11/mezzanine,molokov/mezzanine,ryneeverett/mezzanine,stephenmcd/mezzanine