new_contents: import unittest
  
  from bermann.row import Row
  from bermann.rdd import RDD
  from bermann.dataframe import DataFrame
  
  
  class TestDataFrame(unittest.TestCase):
  
      def test_creation_from_list_of_dicts(self):
          df = DataFrame([
              {'a': 'a', 'b': 123},
              {'a': 'aa', 'b': 456}
          ])
  
          self.assertEqual(df.count(), 2)
  
      def test_creation_from_rdd_of_rows(self):
          rdd = RDD(
              Row(a='a', b=123),
              Row(a='aa', b=456)
          )
  
          df = DataFrame(rdd)
  
          self.assertEqual(df.count(), 2)
  
subject: Add minimal Dataframe test