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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 read_stats(self):
 """ Read current ports statistics from chassis. :return: dictionary {port name {group name, {stat name: stat value}}} """


        self.statistics = TgnObjectsDict()
        for port in self.session.ports.values():
            self.statistics[port] = port.read_port_stats()
        return self.statistics