duplicate_code_names_2.py uses tokenize to print duplicate code names
within the same scope, excluding property setter/getter/deleter
duplicates, excluding duplicates of nested classes or functions, and
ignoring duplicates listed in a file (run with --help for more
details).  With the attached ignored_duplicates file, it prints the
following output on the root of the current default branch (in about 1
mn on an old laptop):

$ ./duplicate_code_names_2.py --ignore ignored_duplicates .
Duplicate function or class names:
./Lib/test/_test_multiprocessing.py:3047 _TestProcess
./Lib/test/test_os.py:1290 Win32ErrorTests

Duplicate method names:
./Lib/ctypes/test/test_functions.py:316 FunctionTestCase.test_errors
./Lib/distutils/tests/test_cmd.py:80 CommandTestCase.test_ensure_string_list
./Lib/lib2to3/tests/test_fixers.py:1467 Test_dict.test_14
./Lib/lib2to3/tests/test_fixers.py:1472 Test_dict.test_15
./Lib/lib2to3/tests/test_fixers.py:1477 Test_dict.test_17
./Lib/lib2to3/tests/test_fixers.py:1482 Test_dict.test_18
./Lib/lib2to3/tests/test_fixers.py:1487 Test_dict.test_19
./Lib/test/test_complex.py:104 ComplexTest.test_truediv
./Lib/test/test_dis.py:250 DisTests.test_big_linenos
./Lib/test/test_dis.py:294 DisTests.test_dis_object
./Lib/test/test_ftplib.py:537 TestFTPClass.test_mkd
./Lib/test/test_heapq.py:366 TestErrorHandling.test_get_only
./Lib/test/test_import.py:255 ImportTests.test_import_name_binding
./Lib/test/test_regrtest.py:210 ParseArgsTestCase.test_findleaks
./Lib/test/test_smtplib.py:249 DebuggingServerTests.testNotImplemented
./Lib/test/test_webbrowser.py:161 OperaCommandTest.test_open_new
./Lib/unittest/test/testmock/testmock.py:1381 MockTest.test_attribute_deletion
./Lib/xml/dom/minidom.py:379 Attr._get_name
./Mac/Tools/Doc/setup.py:123 DocBuild.makeHelpIndex