This is LocaleTextCalendar.__init__

    def __init__(self, firstweekday=0, locale=None):
        TextCalendar.__init__(self, firstweekday)
        if locale is None:
            locale = locale.getdefaultlocale()
        self.locale = locale

Which can not work, obviosly ... let me hilight the important part
        if locale is None:
            locale = locale.getdefaultlocale()
???

Attached is a patch that corrects this and keeps the signature of the
method with the locale=None keyword.