:func:`gmtime` or :func:`localtime` to a string as specified by the *format*
argument. If *t* is not provided, the current time as returned by
:func:`localtime` is used. *format* must be a string. :exc:`ValueError` is
- raised if any field in *t* is outside of the allowed range.
+ raised if any field in *t* is outside of the allowed range. :func:`strftime`
+ returns a locale depedent byte string; the result may be converted to unicode
+ by doing ``strftime(<myformat>).decode(locale.getlocale()[1])``.
.. versionchanged:: 2.1
Allowed *t* to be omitted.