How to use the portage.util.writemsg_level function in portage

for eroot in eroots:
				if need_write_vardb and \
					not trees[eroot]["vartree"].dbapi.writable:
					writemsg_level("!!! %s\n" %
						_("Read-only file system: %s") %
						trees[eroot]["vartree"].dbapi._dbroot,
						level=logging.ERROR, noiselevel=-1)
					return 1

				if need_write_bindb and eroot in ebuild_eroots and \
					("buildpkg" in trees[eroot]["root_config"].
					settings.features or
					"buildsyspkg" in trees[eroot]["root_config"].
					settings.features) and \
					not trees[eroot]["bintree"].dbapi.writable:
					writemsg_level("!!! %s\n" %
						_("Read-only file system: %s") %
						trees[eroot]["bintree"].pkgdir,
						level=logging.ERROR, noiselevel=-1)
					return 1

		if ("--resume" in myopts):
			favorites=mtimedb["resume"]["favorites"]

		else:
			if "resume" in mtimedb and \
			"mergelist" in mtimedb["resume"] and \
			len(mtimedb["resume"]["mergelist"]) > 1:
				mtimedb["resume_backup"] = mtimedb["resume"]
				del mtimedb["resume"]
				mtimedb.commit()

for l in proc.stdout:
					try:
						l = _unicode_decode(l,
							encoding=_encodings['content'], errors='strict')
					except UnicodeDecodeError:
						l = _unicode_decode(l,
							encoding=_encodings['content'], errors='replace')
						writemsg_level(_("\nError decoding characters " \
							"returned from scanmacho: %s\n\n") % (l,),
							level=logging.ERROR, noiselevel=-1)
					l = l.rstrip("\n")
					if not l:
						continue
					fields = l.split(";")
					if len(fields) < 4:
						writemsg_level("\nWrong number of fields " + \
							"returned from scanmacho: %s\n\n" % (l,),
							level=logging.ERROR, noiselevel=-1)
						continue
					fields[1] = fields[1][root_len:]
					owner = plibs.pop(fields[1], None)
					lines.append((owner, "scanmacho", ";".join(fields)))
				proc.wait()
				proc.stdout.close()

		if plibs:
			# Preserved libraries that did not appear in the scanmacho output.
			# This is known to happen with statically linked libraries.
			# Generate dummy lines for these, so we can assume that every
			# preserved library has an entry in self._obj_properties. This
			# is important in order to prevent findConsumers from raising
			# an unwanted KeyError.

try:
				unread = set(grabfile(unread_filename))
				unread_orig = unread.copy()
				skip = set(grabfile(skip_filename))
				skip_orig = skip.copy()
			except PermissionDenied:
				return

			for itemid in news:
				try:
					itemid = _unicode_decode(itemid,
						encoding=_encodings['fs'], errors='strict')
				except UnicodeDecodeError:
					itemid = _unicode_decode(itemid,
						encoding=_encodings['fs'], errors='replace')
					writemsg_level(
						_("!!! Invalid encoding in news item name: '%s'\n") % \
						itemid, level=logging.ERROR, noiselevel=-1)
					continue

				if itemid in skip:
					continue
				filename = os.path.join(news_dir, itemid,
					itemid + "." + self.language_id + ".txt")
				if not os.path.isfile(filename):
					continue
				item = NewsItem(filename, itemid)
				if not item.isValid():
					continue
				if item.isRelevant(profile=self._profile_path,
					config=self.config, vardb=self.vdb):
					unread.add(item.name)

def load(self):
		debug = self._debug
		if debug:
			writemsg_level("\nPackagesSystemSet: profile paths: %s\n" % \
				(self._profile_paths,), level=logging.DEBUG, noiselevel=-1)

		mylist = [grabfile_package(os.path.join(x, "packages"),
							 recursive=True,
							 verify_eapi=True) for x in self._profile_paths]

		if debug:
			writemsg_level("\nPackagesSystemSet: raw packages: %s\n" % \
				(mylist,), level=logging.DEBUG, noiselevel=-1)

		mylist = stack_lists(mylist, incremental=1)

		if debug:
			writemsg_level("\nPackagesSystemSet: stacked packages: %s\n" % \
				(mylist,), level=logging.DEBUG, noiselevel=-1)

def action_deselect(settings, trees, opts, atoms):
	enter_invalid = '--ask-enter-invalid' in opts
	root_config = trees[settings['EROOT']]['root_config']
	world_set = root_config.sets['selected']
	if not hasattr(world_set, 'update'):
		writemsg_level("World @selected set does not appear to be mutable.\n",
			level=logging.ERROR, noiselevel=-1)
		return 1

	pretend = '--pretend' in opts
	locked = False
	if not pretend and hasattr(world_set, 'lock'):
		world_set.lock()
		locked = True
	try:
		world_set.load()
		world_atoms = world_set.getAtoms()
		vardb = root_config.trees["vartree"].dbapi
		expanded_atoms = set(atoms)

		for atom in atoms:
			if not atom.startswith(SETPREFIX):

_hooks = self.hooks["repo.postsync.d"]
		else:
			_hooks = self.hooks["postsync.d"]
		for filepath in _hooks:
			writemsg_level("Spawning post_sync hook: %s\n"
				% (_unicode_decode(_hooks[filepath])),
				level=logging.ERROR, noiselevel=4)
			if reponame:
				retval = portage.process.spawn(
					[filepath, reponame, dosyncuri, repolocation],
					env=self.settings.environ())
			else:
				retval = portage.process.spawn([filepath],
					env=self.settings.environ())
			if retval != os.EX_OK:
				writemsg_level(" %s Spawn failed for: %s, %s\n" % (bad("*"),
					_unicode_decode(_hooks[filepath]), filepath),
					level=logging.ERROR, noiselevel=-1)
				succeeded = retval
		return succeeded

def _writemsg_level(self, msg, level=0, noiselevel=0):

		log_path = self.settings.get("PORTAGE_LOG_FILE")
		background = self.background

		if log_path is None:
			if not (background and level < logging.WARNING):
				portage.util.writemsg_level(msg,
					level=level, noiselevel=noiselevel)
		else:
			self.scheduler.output(msg, log_path=log_path,
				level=level, noiselevel=noiselevel)

read_file = self._parser.readfp

			for p in paths:
				f = None
				try:
					f = io.open(_unicode_encode(p,
						encoding=_encodings['fs'], errors='strict'),
						mode='r', encoding=_encodings['repo.content'],
						errors='replace')
				except EnvironmentError:
					pass
				else:
					try:
						read_file(f)
					except ParsingError as e:
						writemsg_level(_unicode_decode(
							_("!!! Error while reading sets config file: %s\n")
							) % e, level=logging.ERROR, noiselevel=-1)
				finally:
					if f is not None:
						f.close()
		else:
			self._create_default_config()

		self.errors = []
		self.psets = {}
		self.trees = trees
		self.settings = settings
		self._parsed = False
		self.active = []

else:
		missing_sets_str = '"%s"' % missing_sets[-1]
	msg = ["emerge: incomplete set configuration, " + \
		"missing set(s): %s" % missing_sets_str]
	if root_config.sets:
		msg.append("        sets defined: %s" % ", ".join(root_config.sets))
	global_config_path = portage.const.GLOBAL_CONFIG_PATH
	if portage.const.EPREFIX:
		global_config_path = os.path.join(portage.const.EPREFIX,
				portage.const.GLOBAL_CONFIG_PATH.lstrip(os.sep))
	msg.append("        This usually means that '%s'" % \
		(os.path.join(global_config_path, "sets/portage.conf"),))
	msg.append("        is missing or corrupt.")
	msg.append("        Falling back to default world and system set configuration!!!")
	for line in msg:
		writemsg_level(line + "\n", level=logging.ERROR, noiselevel=-1)

writemsg_level(  "Depstring: %s\n"
						% (depstr,), noiselevel=-1, level=logging.DEBUG)
					writemsg_level(  "Priority:  %s\n"
						% (priority,), noiselevel=-1, level=logging.DEBUG)

				try:
					atoms = resolver._select_atoms(eroot, depstr,
						myuse=node.use.enabled, parent=node,
						priority=priority)[node]
				except portage.exception.InvalidDependString:
					# Ignore invalid deps of packages that will
					# be uninstalled anyway.
					continue

				if debug:
					writemsg_level("Candidates: [%s]\n" % \
						', '.join("'%s'" % (x,) for x in atoms),
						noiselevel=-1, level=logging.DEBUG)

				for atom in atoms:
					if not isinstance(atom, portage.dep.Atom):
						# Ignore invalid atoms returned from dep_check().
						continue
					if atom.blocker:
						continue
					matches = vardb.match_pkgs(atom)
					if not matches:
						continue
					for child_node in matches:
						if child_node in clean_set:

							mypriority = priority.copy()