old_contents: import pytest
  
  from mangacork import utils
  
  @pytest.fixture
  def sample_page_bad_format():
      sample_page = {'chapter': "chapter1", 'page': 3}
      return sample_page
  
  @pytest.fixture
  def sample_page_good_format():
      sample_page = {'chapter':'manga_ch1', 'page':'x_v001-001'}
      return sample_page
  
  
  def test_build_img_path(sample_page_bad_format):
      chapter = sample_page_bad_format["chapter"]
      page = sample_page_bad_format["page"]
      expected_output = "/chapter1/3"
      assert utils.build_img_path(chapter,page) == expected_output
  
  def test_increment_page_number_bad_formate(sample_page_bad_format):
      with pytest.raises(ValueError):
          current_page = utils.build_img_path(sample_page_bad_format["chapter"],
                                              sample_page_bad_format["page"])
          utils.increment_page_number(current_page)
  
new_contents: import pytest
  
  from mangacork import utils
  
  @pytest.fixture
  def sample_page_bad_format():
      sample_page = {'chapter': "chapter1", 'page': 3}
      return sample_page
  
  @pytest.fixture
  def sample_page_good_format():
      sample_page = {'chapter':'manga_ch1', 'page':'x_v001-001'}
      return sample_page
  
  def test_build_img_path(sample_page_bad_format):
      chapter = sample_page_bad_format["chapter"]
      page = sample_page_bad_format["page"]
      expected_output = "/chapter1/3"
      assert utils.build_img_path(chapter,page) == expected_output
  
  def test_increment_page_number_bad_format(sample_page_bad_format):
      with pytest.raises(ValueError):
          current_page = utils.build_img_path(sample_page_bad_format["chapter"],
                                              sample_page_bad_format["page"])
          utils.increment_page_number(current_page)
  
  
  def test_increment_page_number_good_format(sample_page_good_format):
      chapter = sample_page_good_format["chapter"]
      page = sample_page_good_format["page"]
      current_page = utils.build_img_path(chapter, page)
      next_page = utils.increment_page_number(current_page)
      expected_output = '/manga_ch1/x_v001-002'
      assert next_page == expected_output
  
subject: Add test for inc page num, good format