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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 list(self, environment_vip=None):
 """List networks redeipv6 ] :param environment_vip: environment vip to filter :return: IPv6 Networks """


        uri = 'api/networkv6/?'
        if environment_vip:
            uri += 'environment_vip=%s' % environment_vip

        return super(ApiNetworkIPv6, self).get(uri)