def tif_to_pdf(self):
        file_obj = self.do_convert('tiff2pdf -o %(to)s %(from)s')
        return ['application/pdf', file_obj]
tiff to pdf conversion, use tiff2pdf command (libtiff)
dataset/ETHPy150Open adlibre/Adlibre-DMS/adlibre_dms/libraries/adlibre/converter.py/NewFileConverter.tif_to_pdf