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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 example_instance(cls, skip=()):
 """ Generate an example instance of a Serializable subclass. If traits have been tagged with an `example` value, then we use that value. Otherwise we fall back the default_value for the instance. Traits with names in ``skip`` will not have example values set. """

        kwargs = {}
        for name, trait in iteritems(cls.class_traits()):
            if name in skip:
                continue
            value = trait.example_value
            if value is Undefined:
                continue
            kwargs[name] = value

        return cls(**kwargs)