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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 from_attribute(attr):
 """ Converts an attribute into a shadow attribute. :param attr: :class:`MispAttribute` instance to be converted :returns: Converted :class:`MispShadowAttribute` :example: """

        assert attr is not MispAttribute
        prop = MispShadowAttribute()
        prop.distribution = attr.distribution
        prop.type = attr.type
        prop.comment = attr.comment
        prop.value = attr.value
        prop.category = attr.category
        prop.to_ids = attr.to_ids
        return prop