In str.join, if any of the iterable contains a Unicode object,
str.join will return a Unicode object.
A Type error will be raised if iterable contains values other
than a string or Unicode object.
.. method:: str.join(iterable)
Return a string which is the concatenation of the strings in *iterable*.
- A :exc:`TypeError` will be raised if there are any non-string values in
- *iterable*, including :class:`bytes` objects. The separator between
- elements is the string providing this method.
+ If there is any Unicode object in *iterable*, return a Unicode instead.
+ A :exc:`TypeError` will be raised if there are any non-string or non Unicode
+ object values in *iterable*. The separator between elements is the string
+ providing this method.
.. method:: str.ljust(width[, fillchar])