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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 normalizeGroupValue(value):
 """ Normalizes group value. * **value** must be a ``list``. * **value** items must normalize as glyph names with :func:`normalizeGlyphName`. * Returned value will be a ``tuple`` of unencoded ``unicode`` strings. """

    if not isinstance(value, (tuple, list)):
        raise TypeError("Group value must be a list, not %s."
                        % type(value).__name__)
    value = [normalizeGlyphName(v) for v in value]
    return tuple([unicode(v) for v in value])