How can I include special characters (tab, newline) in a python doctest result string?

I've gotten this to work using literal string notation for the docstring:

def join_with_tab(iterable):    r"""    >>> join_with_tab(['1', '2'])    '1\t2'    """    return '\t'.join(iterable)if __name__ == "__main__":    import doctest    doctest.testmod()

It's the raw heredoc string notation (r""") that did the trick:

# filename: dedupe.pyimport re,doctestdef dedupe_whitespace(s,spacechars='\t '):    r"""Merge repeated whitespace characters.    Example:    >>> dedupe_whitespace('Black\t\tGround')  #doctest: +REPORT_NDIFF    'Black\tGround'    """    for w in spacechars:        s = re.sub(r"("+w+"+)", w, s)    return sif __name__ == "__main__":    doctest.testmod()

TL;DR: Escape the backslash, i.e., use \\n or \\t instead of \n or \t in your otherwise unmodified strings;

You probably don't want to make your docstrings raw as then you won't be able to use any Python string escapes including those you might want to.

For a method that supports using normal escapes, just escape the backslash in the backslash-character escape so after Python interprets it, it leaves a literal backslash followed by the character which doctest can parse.