'Unescape markup into an text_type string and strip all tags.  This
also resolves known HTML4 and XHTML entities.  Whitespace is
normalized to one:
>>> Markup("Main &raquo;  <em>About</em>").striptags()
u\'Main \xbb About\''

def striptags(self):

    stripped = u'    '.join(_striptags_re.sub('', self).split())
    return Markup(stripped).unescape()
