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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 macho_dependencies_list(target_path, header_magic=None):
 	""" Generates a list of libraries the given Mach-O file depends on. 	In that list a single library is represented by its "install path": for some 	libraries it would be a full file path, and for others it would be a relative 	path (sometimes with dyld templates like @executable_path or @rpath in it). 	Note: I don't know any reason why would some architectures of a fat Mach-O depend 	on certain libraries while others don't, but *it's technically possible*. 	So that's why you may want to specify the `header_magic` value for a particular header. 	Returns an object with two properties: `weak` and `strong` that hold lists of weak 	and strong dependencies respectively. 	"""

	MachODeprendencies = namedtuple("MachODeprendecies", "weak strong")

	# Convert the magic value into macholib representation if needed
	if isinstance(header_magic, basestring):
		header_magic = _MH_MAGIC_from_string(header_magic)

	macho = MachO(target_path)
	# Obtain a list of headers for the required magic value (if any)
	suggestions = filter(lambda t: t.header.magic == header_magic
	                                 or # just add all headers if user didn't specifiy the magic
	                                 header_magic == None, macho.headers)
	header = None if len(suggestions) <= 0 else suggestions[0]
	# filter() above *always* returns a list, so we have to check if it's empty
	if header is None:
		raise Exception("Unable to find a header for the given MAGIC value in that Mach-O file")
		return None

	def decodeLoadCommandData(data):
		# Also ignore trailing zeros
		return data[:data.find(b"\x00")].decode(sys.getfilesystemencoding())

	def strongReferencesFromHeader(h):
		# List of LC_LOAD_DYLIB commands
		list = filter(lambda (lc,cmd,data): lc.cmd == LC_LOAD_DYLIB, h.commands)
		# Their contents (aka data) as a file path
		return map(lambda (lc,cmd,data): decodeLoadCommandData(data), list)

	def weakReferencesFromHeader(h):
		list = filter(lambda (lc,cmd,data): lc.cmd == LC_LOAD_WEAK_DYLIB, h.commands)
		return map(lambda (lc,cmd,data): decodeLoadCommandData(data), list)

	strongRefs = strongReferencesFromHeader(header)
	weakRefs   = weakReferencesFromHeader(header)

	return MachODeprendencies(weak = weakRefs, strong = strongRefs)