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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 in_use_connection_count(self, address):
 """ Count the number of connections currently in use to a given address. """

        try:
            connections = self.connections[address]
        except KeyError:
            return 0
        else:
            return sum(1 if connection.in_use else 0 for connection in connections)