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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 get_children_tag_names(self, xml_element):
 """Returns all tag names of xml element and its children."""

        tags = set()
        tags.add(self.remove_namespace_from_tag(xml_element.tag))

        for element in xml_element.iter(tag=etree.Element):
            if element != xml_element:
                new_tags = self.get_children_tag_names(element)
                if new_tags is not None:
                    tags.update(new_tags)
        return tags