code: def test_missing_ip(self):
      transformer = lore.transformers.GeoIP("test", "accuracy")
      data = pandas.DataFrame({"test": ["127.0.0.2"]})
      transformed = transformer.transform(data)
      self.assertTrue(math.isnan(transformed.iloc[0]))
  
imports: import unittest
  import datetime
  import math
  import numpy
  import pandas
  import lore.transformers
label_desc: Use image node_id 4 for calling the TestGeoIP obj's underlying member method code with example usage: obj.test_missing_ip() without return types