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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 to_python(self, value):
 """ `value` has slashs in it, that's why we inherit from `PathConverter`. E.g.: `commune/13200@latest/`, `departement/13@1860-07-01/` or `region/76@2016-01-01/Auvergne-Rhone-Alpes/`. Note that the slug is not significative but cannot be omitted. """

        if '/' not in value:
            return

        level, code = value.split('/')[:2]  # Ignore optional slug

        geoid = GeoZone.SEPARATOR.join([level, code])
        zone = GeoZone.objects.resolve(geoid)

        if not zone and GeoZone.SEPARATOR not in level:
            # Try implicit default prefix
            level = GeoZone.SEPARATOR.join([self.DEFAULT_PREFIX, level])
            geoid = GeoZone.SEPARATOR.join([level, code])
            zone = GeoZone.objects.resolve(geoid)

        return zone or NotFound()