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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 refresh(self):
 """ Fetches all current network names from the client, along with their id. """

        if not self._client:
            return
        current_networks = self._client.networks()
        self.clear()
        self.update((net['Name'], net['Id'])
                    for net in current_networks)