def _get_list_value_for_modification(self, key):
		try:
			value = self.table[key]
		except KeyError:
			try: value = self.parent[key]
			except AttributeError: value = []
			if isinstance(value, list):
				value = value[:]
			else:
				value = [value]
		else:
			if not isinstance(value, list):
				value = [value]
		self.table[key] = value
		return value
DP. The transition function should be:
dataset/ETHPy150Open appcelerator-archive/poc-nodejs-desktop/Resources/nodejs/builds/linux/node/lib/node/wafadmin/Environment.py/Environment._get_list_value_for_modification--crossover with--dataset/ETHPy150Open algorhythms/LeetCode/069 Climbing Stairs.py/Solution.climbStairs