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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 set_category(self, category):
 """Set the policy's category. Args: category: A category object. """

        pcategory = self.find("general/category")
        pcategory.clear()
        name = ElementTree.SubElement(pcategory, "name")
        if isinstance(category, Category):
            id_ = ElementTree.SubElement(pcategory, "id")
            id_.text = category.id
            name.text = category.name
        elif isinstance(category, basestring):
            name.text = category