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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 read_element_using_argtuple(self, argtuple):
 		""" 		takes a tuple of keys 		returns node found in cfg_dict 		found by traversing cfg_dict by successive 		application of keys from element_path 		"""


		# doesn't support DELIMITED, only dict-based formats
		if self.format == FMT_DELIMITED:
			return None

		node = self.cfg_dict
		for key in argtuple:
			node = node[key]
		return node