test_nonascii has been implemented in issue 16182.

The error message:
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FAIL: test_nonascii (test.test_readline.TestReadline)
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Traceback (most recent call last):
  File "/sdcard/org.bitbucket.pyona/lib/python3.7/test/test_readline.py", line 203, in test_nonascii
    self.assertIn(b"text 't\\xeb'\r\n", output)
AssertionError: b"text 't\\xeb'\r\n" not found in bytearray(b"^A^B^B^B^B^B^B^B\t\tx\t\r\n[\\303\\257nserted]|t\x07\x08\x08\x08\x08\x08\x08\x08\x07\x07xrted]|t\x08\x08\x08\x08\x08\x08\x08\x07\r\nresult \'[\\xefnsexrted]|t\'\r\nhistory \'[\\xefnsexrted]|t\'\r\n")

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