new_contents: import pandas as pd
  import numpy as np
  import unittest
  import geopy as gy
  from geopy.geocoders import Nominatim
  
  import cityfynders.data_processing as dp
  
  
  class DataProcessingTest(unittest.TestCase):
      """
      Please run this test in cityfynders/ dir
      """
  
      def setUp(self):
          print('setUp...')
  
      # test for data_rank
      def test_data_rank(self):
          # [natural, human, economy, tertiary] = dp.read_data()
          natural1 = pd.read_csv('../data/Natural.csv')
          human1 = pd.read_csv('../data/human_related.csv')
          economy1 = pd.read_csv('../data/economy.csv')
          tertiary1 = pd.read_csv("../data/tertiary.csv")
          (natural, human, economy, tertiary) = \
              dp.data_rank(natural1, human1, economy1, tertiary1)
          self.assertTrue(np.isclose(human['Human_related_rank'][0], 27.0))
  
      # test for geopy
      def test_get_loc(self):
          geolocator = Nominatim()
          loc = geolocator.geocode('Beijing' + ' China')
          lat = loc.latitude
          lon = loc.longitude
          self.assertTrue(np.isclose(lat, 39.90596))
  
      # test for find_loc
      def test_find_loc(self):
          # [natural, human, economy, tertiary] = dp.read_data()
          human = pd.read_csv('../data/human_related.csv')
          (Lat, Lon) = dp.find_loc(human)
          self.assertTrue(np.isclose(Lat[0], 33.7490987))
  
      # test for create_rank
      def test_create_rank(self):
          # [natural, human, economy, tertiary] = dp.read_data()
          natural1 = pd.read_csv('../data/Natural.csv')
          human1 = pd.read_csv('../data/human_related.csv')
          economy1 = pd.read_csv('../data/economy.csv')
          tertiary1 = pd.read_csv("../data/tertiary.csv")
          (natural, human, economy, tertiary) = \
              dp.data_rank(natural1, human1, economy1, tertiary1)
          rank1 = pd.read_csv('../data/rank_file.csv')
          Lat = rank1['Latitude']
          Lon = rank1['Longitude']
          rank = dp.create_rank(natural, human, economy, tertiary, Lat, Lon)
          self.assertTrue(np.isclose(rank['Economy_rank'][0], 34.0))
  
      def tearDown(self):
          print('tearDown...')
  
  
  if __name__ == '__main__':
      unittest.main()
  
subject: add tests for data_processing