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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 recurse_up(directory, filename):
 	""" 	Recursive walk a directory up to root until it contains `filename` 	"""


	directory = osp.abspath(directory)

	while True:
		searchfile = osp.join(directory, filename)

		if osp.isfile(searchfile):
			return directory

		if directory == '/': break
		else: directory = osp.dirname(directory)
	return False