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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 _parse_default(self, target):
 """Helper function to parse default values."""

        if not isinstance(target, (list, tuple)):
            k, v, t = target, None, lambda x: x
        elif len(target) == 1:
            k, v, t = target[0], None, lambda x: x
        elif len(target) == 2:
            k, v, t = target[0], target[1], lambda x: x
        elif len(target) > 2:
            k, v, t = target[0], target[1], target[2]
        else:
            k = None  # should raise
        if not isinstance(k, string_types):
            msg = "{} is not a valid target, (name, default) expected.".format(target)
            raise ValueError(msg)
        return k, v, t