human
Complete this python program:
def _get_unicode_checker():
assistant
#Here is the Python program you requested.

    """Returns a doctest.OutputChecker subclass that takes in account the
    ALLOW_UNICODE option to ignore u\\ prefixes in strings. Useful
    when the same doctest should run in Python 2 and Python 3.
    An inner class is used to avoid importing "doctest" at the module
    level.
    """
    if hasattr(_get_unicode_checker, 'UnicodeOutputChecker'):
        return _get_unicode_checker.UnicodeOutputChecker()
    import doctest
    import re
    class UnicodeOutputChecker(doctest.OutputChecker, ):
        '\n                                Copied    from    doctest_nose_plugin.py    from    the    nltk    project:\n                                                https://github.com/nltk/nltk\n                                '
        _literal_re = re.compile('(\\W|^)[uU]([rR]?[\\\'\\"])', re.UNICODE)
        def check_output(self, want, got, optionflags):
            res = doctest.OutputChecker.check_output(self, want, got, optionflags)
            if res:
                return True
            if (not (optionflags & _get_allow_unicode_flag())):
                return False
            else:
                def remove_u_prefixes(txt):
                    return re.sub(self._literal_re, '\\1\\2', txt)
                want = remove_u_prefixes(want)
                got = remove_u_prefixes(got)
                res = doctest.OutputChecker.check_output(self, want, got, optionflags)
                return res
    _get_unicode_checker.UnicodeOutputChecker = UnicodeOutputChecker
    return _get_unicode_checker.UnicodeOutputChecker()