old_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  
  # pyvows testing engine
  # https://github.com/heynemann/pyvows
  
  # Licensed under the MIT license:
  # http://www.opensource.org/licenses/mit-license
  # Copyright (c) 2011 Bernardo Heynemann heynemann@gmail.com
  
  from pyvows import Vows, expect
  
  def get_test_data():
      for i in [1] * 10:
          yield i
  
  @Vows.batch
  class GeneratorTests(Vows.Context):
      def topic(self):
          return get_test_data()
  
      def should_be_numeric(self, topic):
          expect(topic).to_equal(1)
  
      class SubContext(Vows.Context):
          def topic(self, parent_topic):
              return parent_topic
  
          def should_be_executed_many_times(self, topic):
              expect(topic).to_equal(1)
  
          class SubSubContext(Vows.Context):
              def topic(self, parent_topic, outer_topic):
                  return outer_topic
  
              def should_be_executed_many_times(self, topic):
                  expect(topic).to_equal(1)
  
      class GeneratorAgainContext(Vows.Context):
          def topic(self, topic):
              for i in range(10):
                  yield topic * 2
  
          def should_return_topic_times_two(self, topic):
              expect(topic).to_equal(2)
  
  def add(a, b):
      return a + b
  
  a_samples = range(10)
  b_samples = range(10)
  
  @Vows.batch
  class Add(Vows.Context):
      class ATopic(Vows.Context):
          def topic(self):
              for a in a_samples:
                  yield a
  
          class BTopic(Vows.Context):
              def topic(self, a):
                  for b in b_samples:
                      yield b
  
              class Sum(Vows.Context):
                  def topic(self, b, a):
                      yield (add(a, b), a + b)
  
                  def should_be_numeric(self, topic):
                      value, expected = topic
                      expect(value).to_be_numeric()
  
                  def should_equal_to_expected(self, topic):
                      value, expected = topic
                      expect(value).to_equal(expected)
  
  
new_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  
  # pyvows testing engine
  # https://github.com/heynemann/pyvows
  
  # Licensed under the MIT license:
  # http://www.opensource.org/licenses/mit-license
  # Copyright (c) 2011 Bernardo Heynemann heynemann@gmail.com
  
  from pyvows import Vows, expect
  
  
  def get_test_data():
      for i in [1] * 10:
          yield i
  
  
  @Vows.batch
  class GeneratorTests(Vows.Context):
      def topic(self):
          return get_test_data()
  
      def should_be_numeric(self, topic):
          expect(topic).to_equal(1)
  
      class SubContext(Vows.Context):
          def topic(self, parent_topic):
              return parent_topic
  
          def should_be_executed_many_times(self, topic):
              expect(topic).to_equal(1)
  
          class SubSubContext(Vows.Context):
              def topic(self, parent_topic, outer_topic):
                  return outer_topic
  
              def should_be_executed_many_times(self, topic):
                  expect(topic).to_equal(1)
  
      class GeneratorAgainContext(Vows.Context):
          def topic(self, topic):
              for i in range(10):
                  yield topic * 2
  
          def should_return_topic_times_two(self, topic):
              expect(topic).to_equal(2)
  
  
  def add(a, b):
      return a + b
  
  a_samples = range(10)
  b_samples = range(10)
  
  
  @Vows.batch
  class Add(Vows.Context):
      class ATopic(Vows.Context):
          def topic(self):
              for a in a_samples:
                  yield a
  
          class BTopic(Vows.Context):
              def topic(self, a):
                  for b in b_samples:
                      yield b
  
              class Sum(Vows.Context):
                  def topic(self, b, a):
                      yield (add(a, b), a + b)
  
                  def should_be_numeric(self, topic):
                      value, expected = topic
                      expect(value).to_be_numeric()
  
                  def should_equal_to_expected(self, topic):
                      value, expected = topic
                      expect(value).to_equal(expected)
  
subject: add whitespace before classes and functions and remove additional lines at the end of the file for flake8