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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_theming_attribute(self, mode, name, part=None):
 """ looks up theming attribute :type mode: str :param name: identifier of the atttribute :type name: str :rtype: urwid.AttrSpec """

        colours = int(self._config.get('colourmode'))
        return self._theme.get_attribute(colours, mode, name, part)