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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 normalizeKerningKey(value):
 """ Normalizes kerning key. * **value** must be a ``tuple`` or ``list``. * **value** must contain only two members. * **value** items must be :ref:`type-string`. * **value** items must be at least one character long. * Returned value will be a two member ``tuple`` of unencoded ``unicode`` strings. """

    if not isinstance(value, (tuple, list)):
        raise TypeError("Kerning key must be a tuple instance, not %s."
                        % type(value).__name__)
    if len(value) != 2:
        raise ValueError("Kerning key must be a tuple containing two items, "
                         "not %d." % len(value))
    for v in value:
        if not isinstance(v, basestring):
            raise TypeError("Kerning key items must be strings, not %s."
                            % type(v).__name__)
        if len(v) < 1:
            raise ValueError("Kerning key items must be one character long")
    if value[0].startswith("public.") and not value[0].startswith(
            "public.kern1."):
        raise ValueError("Left Kerning key group must start with "
                         "public.kern1.")
    if value[1].startswith("public.") and not value[1].startswith(
            "public.kern2."):
        raise ValueError("Right Kerning key group must start with "
                         "public.kern2.")
    return tuple([unicode(v) for v in value])