I was thinking about contributing to cpython so i cloned it and followed the tests mentioned on devguide.python.org. When i ran my tests, it failed on two of them: test_pdb and test_ssl. test_ssl had an issue already as i found here. test_pdb failure was the one which i didn't find here. It failed with the following message:

== CPython 3.10.0a0 (heads/master:a937ab45d6, Oct 3 2020, 00:16:29) [GCC 9.3.0]
== Linux-5.4.0-48-generic-x86_64-with-glibc2.31 little-endian
== cwd: /mnt/sda2/github/cpython/build/test_python_21809æ
== CPU count: 4
== encodings: locale=UTF-8, FS=utf-8
0:00:00 load avg: 1.52 Run tests in parallel using 2 child processes
0:00:06 load avg: 1.48 [1/1/1] test_pdb failed
test_blocks_at_first_code_line (test.test_pdb.PdbTestCase) ... ok
test_breakpoint (test.test_pdb.PdbTestCase) ... ok
test_errors_in_command (test.test_pdb.PdbTestCase) ... FAIL
test_find_function_empty_file (test.test_pdb.PdbTestCase) ... ok
test_find_function_found (test.test_pdb.PdbTestCase) ... ok
test_find_function_found_with_bom (test.test_pdb.PdbTestCase) ... ok
test_find_function_found_with_encoding_cookie (test.test_pdb.PdbTestCase) ... ok
test_header (test.test_pdb.PdbTestCase) ... ok
test_issue13120 (test.test_pdb.PdbTestCase) ... ok
test_issue13183 (test.test_pdb.PdbTestCase) ... ok
test_issue16180 (test.test_pdb.PdbTestCase) ... ok
test_issue36250 (test.test_pdb.PdbTestCase) ... ok
test_issue7964 (test.test_pdb.PdbTestCase) ... ok
test_module_is_run_as_main (test.test_pdb.PdbTestCase) ... ok
test_module_without_a_main (test.test_pdb.PdbTestCase) ... ok
test_readrc_homedir (test.test_pdb.PdbTestCase) ... ok
test_readrc_kwarg (test.test_pdb.PdbTestCase) ... ok
test_relative_imports (test.test_pdb.PdbTestCase) ... ok
test_relative_imports_on_plain_module (test.test_pdb.PdbTestCase) ... ok
test_run_module (test.test_pdb.PdbTestCase) ... ok
test_run_pdb_with_pdb (test.test_pdb.PdbTestCase) ... ok
test_list_commands (test.test_pdb)
Doctest: test.test_pdb.test_list_commands ... ok
test_next_until_return_at_return_event (test.test_pdb)
Doctest: test.test_pdb.test_next_until_return_at_return_event ... ok
test_pdb_basic_commands (test.test_pdb)
Doctest: test.test_pdb.test_pdb_basic_commands ... ok
test_pdb_breakpoint_commands (test.test_pdb)
Doctest: test.test_pdb.test_pdb_breakpoint_commands ... ok
test_pdb_continue_in_bottomframe (test.test_pdb)
Doctest: test.test_pdb.test_pdb_continue_in_bottomframe ... ok
test_pdb_displayhook (test.test_pdb)
Doctest: test.test_pdb.test_pdb_displayhook ... ok
test_pdb_issue_20766 (test.test_pdb)
Doctest: test.test_pdb.test_pdb_issue_20766 ... ok
test_pdb_next_command_for_asyncgen (test.test_pdb)
Doctest: test.test_pdb.test_pdb_next_command_for_asyncgen ... ok
test_pdb_next_command_for_coroutine (test.test_pdb)
Doctest: test.test_pdb.test_pdb_next_command_for_coroutine ... ok
test_pdb_next_command_for_generator (test.test_pdb)
Doctest: test.test_pdb.test_pdb_next_command_for_generator ... ok
test_pdb_next_command_in_generator_for_loop (test.test_pdb)
Doctest: test.test_pdb.test_pdb_next_command_in_generator_for_loop ... ok
test_pdb_next_command_subiterator (test.test_pdb)
Doctest: test.test_pdb.test_pdb_next_command_subiterator ... ok
test_pdb_return_command_for_coroutine (test.test_pdb)
Doctest: test.test_pdb.test_pdb_return_command_for_coroutine ... ok
test_pdb_return_command_for_generator (test.test_pdb)
Doctest: test.test_pdb.test_pdb_return_command_for_generator ... ok
test_pdb_run_with_code_object (test.test_pdb)
Doctest: test.test_pdb.test_pdb_run_with_code_object ... ok
test_pdb_run_with_incorrect_argument (test.test_pdb)
Doctest: test.test_pdb.test_pdb_run_with_incorrect_argument ... ok
test_pdb_skip_modules (test.test_pdb)
Doctest: test.test_pdb.test_pdb_skip_modules ... ok
test_pdb_skip_modules_with_callback (test.test_pdb)
Doctest: test.test_pdb.test_pdb_skip_modules_with_callback ... ok
test_pdb_until_command_for_coroutine (test.test_pdb)
Doctest: test.test_pdb.test_pdb_until_command_for_coroutine ... ok
test_pdb_until_command_for_generator (test.test_pdb)
Doctest: test.test_pdb.test_pdb_until_command_for_generator ... ok
test_pdb_whatis_command (test.test_pdb)
Doctest: test.test_pdb.test_pdb_whatis_command ... ok
test_post_mortem (test.test_pdb)
Doctest: test.test_pdb.test_post_mortem ... ok

======================================================================
FAIL: test_errors_in_command (test.test_pdb.PdbTestCase)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/mnt/sda2/github/cpython/Lib/test/test_pdb.py", line 1650, in test_errors_in_command
    self.assertEqual(stdout.splitlines()[1:], [
AssertionError: Lists differ: ['(Pd[283 chars]efined", 'LEAVING RECURSIVE DEBUGGER', '(Pdb) ', '\x1b[?1034h'] != ['(Pd[283 chars]efined", 'LEAVING RECURSIVE DEBUGGER', '(Pdb) ']

First list contains 1 additional elements.
First extra element 9:
'\x1b[?1034h'

  ['(Pdb) *** SyntaxError: unexpected EOF while parsing',
   '(Pdb) ENTERING RECURSIVE DEBUGGER',
   '*** SyntaxError: unexpected EOF while parsing',
   'LEAVING RECURSIVE DEBUGGER',
   '(Pdb) ENTERING RECURSIVE DEBUGGER',
   '> <string>(1)<module>()',
   "((Pdb)) *** NameError: name 'doesnotexist' is not defined",
   'LEAVING RECURSIVE DEBUGGER',
-  '(Pdb) ',
?          ^

+  '(Pdb) ']
?          ^

-  '\x1b[?1034h']

----------------------------------------------------------------------

Ran 43 tests in 5.143s

FAILED (failures=1)
test test_pdb failed

== Tests result: FAILURE ==

1 test failed:
    test_pdb

Total duration: 6.8 sec
Tests result: FAILURE

Is this happening only with me?