old_contents: import os
  import shutil
  import unittest
  from collections import namedtuple
  
  from conans.client.generators.cmake_paths import CMakePathsGenerator
  from conans.model.build_info import CppInfo
  from conans.model.conan_file import ConanFile
  from conans.model.env_info import EnvValues
  from conans.test.utils.test_files import temp_folder
  from conans.test.utils.tools import TestClient
  
  
  class CMakePathsGeneratorTest(unittest.TestCase):
  
      def cmake_vars_unit_test(self):
          settings_mock = namedtuple("Settings", "build_type, os, os_build, constraint")
          settings = settings_mock("Release", None, None, lambda x, raise_undefined_field: x)
          conanfile = ConanFile(None, None)
          conanfile.initialize(settings, EnvValues())
          tmp = temp_folder()
          cpp_info = CppInfo(tmp)
          custom_dir = os.path.join(tmp, "custom_build_dir")
          os.mkdir(custom_dir)
          cpp_info.builddirs.append(os.path.join(tmp, "custom_build_dir"))
          conanfile.deps_cpp_info.update(cpp_info, "MyLib")
  
          generator = CMakePathsGenerator(conanfile)
          cmake_lines = [s.replace("\t\t\t", "").replace('\\', '/')
                         for s in generator.content.splitlines()]
          self.assertEquals('set(CMAKE_MODULE_PATH '
                            '"%s/"' % tmp.replace('\\', '/'), cmake_lines[0])
          self.assertEquals('"%s" ${CMAKE_MODULE_PATH} '
                            '${CMAKE_CURRENT_LIST_DIR})' % custom_dir.replace('\\', '/'),
                            cmake_lines[1])
          self.assertEquals('set(CMAKE_PREFIX_PATH '
                            '"%s/"' % tmp.replace('\\', '/'), cmake_lines[2])
          self.assertEquals('"%s" ${CMAKE_PREFIX_PATH} '
                            '${CMAKE_CURRENT_LIST_DIR})' % custom_dir.replace('\\', '/'),
                            cmake_lines[3])
  
new_contents: import os
  import shutil
  import unittest
  from collections import namedtuple
  
  from conans.client.generators.cmake_paths import CMakePathsGenerator
  from conans.model.build_info import CppInfo
  from conans.model.conan_file import ConanFile
  from conans.model.env_info import EnvValues
  from conans.test.utils.test_files import temp_folder
  from conans.test.utils.tools import TestClient
  
  
  class CMakePathsGeneratorTest(unittest.TestCase):
  
      def cmake_vars_unit_test(self):
          settings_mock = namedtuple("Settings", "build_type, os, os_build, constraint")
          settings = settings_mock("Release", None, None, lambda x: x)
          conanfile = ConanFile(None, None)
          conanfile.initialize(settings, EnvValues())
          tmp = temp_folder()
          cpp_info = CppInfo(tmp)
          custom_dir = os.path.join(tmp, "custom_build_dir")
          os.mkdir(custom_dir)
          cpp_info.builddirs.append(os.path.join(tmp, "custom_build_dir"))
          conanfile.deps_cpp_info.update(cpp_info, "MyLib")
  
          generator = CMakePathsGenerator(conanfile)
          cmake_lines = [s.replace("\t\t\t", "").replace('\\', '/')
                         for s in generator.content.splitlines()]
          self.assertEquals('set(CMAKE_MODULE_PATH '
                            '"%s/"' % tmp.replace('\\', '/'), cmake_lines[0])
          self.assertEquals('"%s" ${CMAKE_MODULE_PATH} '
                            '${CMAKE_CURRENT_LIST_DIR})' % custom_dir.replace('\\', '/'),
                            cmake_lines[1])
          self.assertEquals('set(CMAKE_PREFIX_PATH '
                            '"%s/"' % tmp.replace('\\', '/'), cmake_lines[2])
          self.assertEquals('"%s" ${CMAKE_PREFIX_PATH} '
                            '${CMAKE_CURRENT_LIST_DIR})' % custom_dir.replace('\\', '/'),
                            cmake_lines[3])
  
subject: fix lambda