def to_xml(self):
		tag = self.XML_REFL.tag
		assert tag is not None, "Must define 'tag' in reflection to use this function"
		doc = etree.Element(tag)
		self.write_xml(doc)
		return doc
Return a matrix formed by joining args vertically (i.e.
dataset/ETHPy150Open RobotLocomotion/director/src/python/urdf_parser_py/xml_reflection/core.py/Object.to_xml--crossover with--dataset/ETHPy150Open sympy/sympy/sympy/matrices/matrices.py/MatrixBase.vstack