$ LC_ALL=es_US.iso88591 ./python -m test -v -m test_syntax_error_for_string test_peg_generator
...
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ERROR: test_syntax_error_for_string (test.test_peg_generator.test_c_parser.TestCParser)
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Traceback (most recent call last):
  File "/home/serhiy/py/cpython/Lib/test/test_peg_generator/test_c_parser.py", line 377, in test_syntax_error_for_string
    self.run_test(grammar_source, test_source)
  File "/home/serhiy/py/cpython/Lib/test/test_peg_generator/test_c_parser.py", line 85, in run_test
    assert_python_ok(
  File "/home/serhiy/py/cpython/Lib/test/support/script_helper.py", line 156, in assert_python_ok
    return _assert_python(True, *args, **env_vars)
  File "/home/serhiy/py/cpython/Lib/test/support/script_helper.py", line 140, in _assert_python
    res, cmd_line = run_python_until_end(*args, **env_vars)
  File "/home/serhiy/py/cpython/Lib/test/support/script_helper.py", line 127, in run_python_until_end
    proc = subprocess.Popen(cmd_line, stdin=subprocess.PIPE,
  File "/home/serhiy/py/cpython/Lib/subprocess.py", line 947, in __init__
    self._execute_child(args, executable, preexec_fn, close_fds,
  File "/home/serhiy/py/cpython/Lib/subprocess.py", line 1752, in _execute_child
    self.pid = _posixsubprocess.fork_exec(
UnicodeEncodeError: 'latin-1' codec can't encode character '\u540d' in position 962: ordinal not in range(256)

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