Comment 4 for bug 1522052

This bug is still there in 3.8.0, with slightly different line numbers:

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ERROR: test_etree_parse_io_error (lxml.tests.test_io.ETreeIOTestCase)
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Traceback (most recent call last):
  File "/usr/pkg/lib/python3.6/unittest/case.py", line 59, in testPartExecutor
    yield
  File "/usr/pkg/lib/python3.6/unittest/case.py", line 605, in run
    testMethod()
  File "/scratch/textproc/py-lxml/work/lxml-3.8.0/src/lxml/tests/test_io.py", line 276, in test_etree_parse_io_error
    dn = tempfile.mkdtemp(prefix=dirnameRU)
  File "/usr/pkg/lib/python3.6/tempfile.py", line 368, in mkdtemp
    _os.mkdir(file, 0o700)
UnicodeEncodeError: 'ascii' codec can't encode characters in position 5-18: ordinal not in range(128)

======================================================================
ERROR: test_etree_parse_io_error (lxml.tests.test_io.ElementTreeIOTestCase)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/pkg/lib/python3.6/unittest/case.py", line 59, in testPartExecutor
    yield
  File "/usr/pkg/lib/python3.6/unittest/case.py", line 605, in run
    testMethod()
  File "/scratch/textproc/py-lxml/work/lxml-3.8.0/src/lxml/tests/test_io.py", line 276, in test_etree_parse_io_error
    dn = tempfile.mkdtemp(prefix=dirnameRU)
  File "/usr/pkg/lib/python3.6/tempfile.py", line 368, in mkdtemp
    _os.mkdir(file, 0o700)
UnicodeEncodeError: 'ascii' codec can't encode characters in position 5-18: ordinal not in range(128)