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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 associate(self, environment_id, environment_vip_id):
 """Associate a news Environment on Environment VIP and returns its identifier. :param environment_id: Identifier of the Environment. Integer value and greater than zero. :param environment_vip_id: Identifier of the Environment VIP. Integer value and greater than zero. :return: Following dictionary: :: {'environment_environment_vip': {'id': < id >}} :raise InvalidParameterError: The value of environment_id or environment_vip_id is invalid. :raise DataBaseError: Networkapi failed to access the database. :raise XMLError: Networkapi failed to generate the XML response. """

        if not is_valid_int_param(environment_id):
            raise InvalidParameterError(
                u'The identifier of Environment VIP is invalid or was not informed.')

        if not is_valid_int_param(environment_vip_id):
            raise InvalidParameterError(
                u'The identifier of Environment is invalid or was not informed.')

        environment_environment_vip_map = dict()
        environment_environment_vip_map['environment_id'] = environment_id
        environment_environment_vip_map['environment_vip_id'] = environment_vip_id

        url = 'environment/{}/environmentvip/{}/'.format(environment_id, environment_vip_id)

        code, xml = self.submit(None, 'PUT', url)

        return self.response(code, xml)