How to use the azure-servicemanagement-legacy.azure.servicemanagement._internal._str function in azure-servicemanagement-legacy

def _get_get_supported_metrics_queue_path(self, namespace_name, queue_name):
        return self._get_path('services/serviceBus/Namespaces/',
                              namespace_name) + '/Queues/' + _str(queue_name) + '/Metrics'

def _get_get_supported_metrics_relay_path(self, namespace_name, queue_name):
        return self._get_path('services/serviceBus/Namespaces/',
                              namespace_name) + '/Relays/' + _str(queue_name) + '/Metrics'

def _get_get_supported_metrics_hub_path(self, namespace_name, hub_name):
        return self._get_path('services/serviceBus/Namespaces/',
                              namespace_name) + '/NotificationHubs/' + _str(hub_name) + '/Metrics'

def _get_get_metrics_data_hub_path(self, namespace_name, queue_name, metric, rollup, filter_expr):
        return "".join([
            self._get_path('services/serviceBus/Namespaces/', namespace_name),
            '/NotificationHubs/',
            _str(queue_name),
            '/Metrics/',
            _str(metric),
            '/Rollups/',
            _str(rollup),
            '/Values?',
            filter_expr
        ])

def _get_get_metrics_data_topic_path(self, namespace_name, queue_name, metric, rollup, filter_expr):
        return "".join([
            self._get_path('services/serviceBus/Namespaces/', namespace_name),
            '/Topics/',
            _str(queue_name),
            '/Metrics/',
            _str(metric),
            '/Rollups/',
            _str(rollup),
            '/Values?',
            filter_expr
        ])

def _get_get_metrics_data_queue_path(self, namespace_name, queue_name, metric, rollup, filter_expr):
        return "".join([
            self._get_path('services/serviceBus/Namespaces/', namespace_name),
            '/Queues/',
            _str(queue_name),
            '/Metrics/',
            _str(metric),
            '/Rollups/',
            _str(rollup),
            '/Values?',
            filter_expr
        ])

def _get_get_metrics_data_topic_path(self, namespace_name, queue_name, metric, rollup, filter_expr):
        return "".join([
            self._get_path('services/serviceBus/Namespaces/', namespace_name),
            '/Topics/',
            _str(queue_name),
            '/Metrics/',
            _str(metric),
            '/Rollups/',
            _str(rollup),
            '/Values?',
            filter_expr
        ])

def _get_get_metrics_data_relay_path(self, namespace_name, queue_name, metric, rollup, filter_expr):
        return "".join([
            self._get_path('services/serviceBus/Namespaces/', namespace_name),
            '/Relays/',
            _str(queue_name),
            '/Metrics/',
            _str(metric),
            '/Rollups/',
            _str(rollup),
            '/Values?',
            filter_expr
        ])

def _get_get_metrics_data_hub_path(self, namespace_name, queue_name, metric, rollup, filter_expr):
        return "".join([
            self._get_path('services/serviceBus/Namespaces/', namespace_name),
            '/NotificationHubs/',
            _str(queue_name),
            '/Metrics/',
            _str(metric),
            '/Rollups/',
            _str(rollup),
            '/Values?',
            filter_expr
        ])