def _content_type__set(self, value):
        if value not in ';':
            if 'content-type' in self._headers:
                header = self._headers.get('content-type')
                if ';' in header[1]:
                    params = header[1].split(';', 1)[1]
                    value += ';' + params
        self['Content-Type'] = value
dataset/ETHPy150Open benoitc/dj-webmachine/webmachine/wrappers.py/WMResponse._content_type__set/swapped operands of `not in`