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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 get_zipcodes_for_canton(self, canton):
 """ Return the list of zipcodes for the given canton code. """

        zipcodes = [
            zipcode for zipcode, location in self.get_locations().items()
            if location.canton == canton
        ]

        return zipcodes