docstr: Tests that the plugin offers the correct routes.
code: def test_routes_provided(self):
      """Tests that the plugin offers the correct routes."""
      routes = self._plugin.get_plugin_apps()
      self.assertIsInstance(routes["/tags"], collections.abc.Callable)
  
imports: import argparse
  import collections.abc
  import os.path
  import tensorflow.compat.v1
  import tensorflow.compat.v2
  from tensorboard import context
  from tensorboard.backend.event_processing import data_provider
  from tensorboard.backend.event_processing import plugin_event_multiplexer
  from tensorboard.data import provider
  from tensorboard.plugins import base_plugin
  from tensorboard.plugins.image import metadata
  from tensorboard.plugins.metrics import metrics_plugin
label_desc: Use image node_id 9 for calling the MetricsPluginTest obj's underlying member method code with example usage: obj.test_routes_provided() without return types