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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 __set_ethernet_uris(self, ethernet_names, operation="add"):
 """Updates network uris."""

        if not isinstance(ethernet_names, list):
            ethernet_names = [ethernet_names]

        associated_enets = self.data.get('networkUris', [])
        ethernet_uris = []

        for i, enet in enumerate(ethernet_names):
            enet_exists = self._ethernet_networks.get_by_name(enet)
            if enet_exists:
                ethernet_uris.append(enet_exists.data['uri'])
            else:
                raise HPOneViewResourceNotFound("Ethernet: {} does not exist".foramt(enet))

        if operation == "remove":
            enets_to_update = sorted(list(set(associated_enets) - set(ethernet_uris)))
        elif operation == "add":
            enets_to_update = sorted(list(set(associated_enets).union(set(ethernet_uris))))
        else:
            raise ValueError("Value {} is not supported as operation. The supported values are: ['add', 'remove']")

        if set(enets_to_update) != set(associated_enets):
            updated_network = {'networkUris': enets_to_update}
            self.update(updated_network)