code: def test_count_values(self):
      d = fo.Dataset()
      s = fo.Sample(filepath="image.jpeg")
      s.tags += ["one", "two"]  # pylint: disable=no-member
      d.add_sample(s)
      self.assertEqual(d.count_values("tags"), {"one": 1, "two": 1})
  
      d = fo.Dataset()
      s = fo.Sample(filepath="video.mp4")
      s["classifications"] = fo.Classifications(
          classifications=[
              fo.Classification(label="one"),
              fo.Classification(label="two"),
              fo.Classification(label="two"),
          ]
      )
      s[1]["classifications"] = fo.Classifications(
          classifications=[
              fo.Classification(label="one"),
              fo.Classification(label="two"),
              fo.Classification(label="two"),
          ]
      )
      s["classification"] = fo.Classification(label="one")
      d.add_sample(s)
      self.assertEqual(
          d.count_values("classification.label"), {"one": 1}
      )
      self.assertEqual(
          d.count_values("classifications.classifications.label"),
          {"one": 1, "two": 2},
      )
      self.assertEqual(
          d.count_values(
              F("classifications.classifications.label").upper()
          ),
          {"ONE": 1, "TWO": 2},
      )
      self.assertEqual(
          d.count_values(
              "frames.classifications.classifications.label"
          ),
          {"one": 1, "two": 2},
      )
      self.assertEqual(
          d.count_values(
              F("frames.classifications.classifications.label").upper()
          ),
          {"ONE": 1, "TWO": 2},
      )
  
      self.assertEqual(
          d.count_values("classifications.classifications[].label"),
          {"one": 1, "two": 2},
      )
      self.assertEqual(
          d.count_values(
              F("classifications.classifications[].label").upper()
          ),
          {"ONE": 1, "TWO": 2},
      )
      self.assertEqual(
          d.count_values(
              "frames[].classifications.classifications[].label"
          ),
          {"one": 1, "two": 2},
      )
      self.assertEqual(
          d.count_values(
              F(
                  "frames[].classifications.classifications[].label"
              ).upper()
          ),
          {"ONE": 1, "TWO": 2},
      )
  
imports: from datetime import date, datetime, timedelta
  import math
  from bson import ObjectId
  import numpy
  import unittest
  import fiftyone
  import fiftyone.core.fields
  from fiftyone import ViewField
  from decorators import drop_datasets
label_desc: Use image node_id 3 for calling the DatasetTests obj's underlying member method code with example usage: obj.test_count_values() without return types