diff --git a/buildVars.py b/buildVars.py
index 5326262..6a2f812 100644
--- a/buildVars.py
+++ b/buildVars.py
@@ -3,15 +3,19 @@
 # Build customizations
 # Change this file instead of sconstruct or manifest files, whenever possible.
 
+
 # Full getext (please don't change)
-_ = lambda x: x
+def _(arg):
+	return arg
+
 
 # Add-on information variables
 addon_info = {
 	# add-on Name/identifier, internal for NVDA
 	"addon_name": "addonTemplate",
 	# Add-on summary, usually the user visible name of the addon.
-	# Translators: Summary for this add-on to be shown on installation and add-on information found in Add-ons Manager.
+	# Translators: Summary for this add-on
+	# to be shown on installation and add-on information found in Add-ons Manager.
 	"addon_summary": _("Add-on user visible name"),
 	# Add-on description
 	# Translators: Long description to be shown for this add-on on add-on information from add-ons manager
@@ -29,12 +33,15 @@
 	"addon_minimumNVDAVersion": None,
 	# Last NVDA version supported/tested (e.g. "2018.4.0", ideally more recent than minimum version)
 	"addon_lastTestedNVDAVersion": None,
-	# Add-on update channel (default is None, denoting stable releases, and for development releases, use "dev"; do not change unless you know what you are doing)
+	# Add-on update channel (default is None, denoting stable releases,
+	# and for development releases, use "dev".)
+	# Do not change unless you know what you are doing!
 	"addon_updateChannel": None,
 }
 
 
-import os.path
+import os.path  # NOQA
+
 
 # Define the python files that are the sources of your add-on.
 # You can use glob expressions here, they will be expanded.
diff --git a/sconstruct b/sconstruct
index cd0e5e8..47aa8ff 100644
--- a/sconstruct
+++ b/sconstruct
@@ -13,10 +13,13 @@ sys.dont_write_bytecode = True
 
 import buildVars
 
+
 def md2html(source, dest):
 	import markdown
 	lang = os.path.basename(os.path.dirname(source)).replace('_', '-')
-	title="{addonSummary} {addonVersion}".format(addonSummary=buildVars.addon_info["addon_summary"], addonVersion=buildVars.addon_info["addon_version"])
+	title = "{addonSummary} {addonVersion}".format(
+		addonSummary=buildVars.addon_info["addon_summary"], addonVersion=buildVars.addon_info["addon_version"]
+	)
 	headerDic = {
 		"[[!meta title=\"": "# ",
 		"\"]]": " #",
@@ -39,17 +42,19 @@ def md2html(source, dest):
 		f.write(htmlText)
 		f.write("\n</body>\n</html>")
 
+
 def mdTool(env):
-	mdAction=env.Action(
-		lambda target,source,env: md2html(source[0].path, target[0].path),
-		lambda target,source,env: 'Generating %s'%target[0],
+	mdAction = env.Action(
+		lambda target, source, env: md2html(source[0].path, target[0].path),
+		lambda target, source, env: 'Generating % s' % target[0],
 	)
-	mdBuilder=env.Builder(
+	mdBuilder = env.Builder(
 		action=mdAction,
 		suffix='.html',
 		src_suffix='.md',
 	)
-	env['BUILDERS']['markdown']=mdBuilder
+	env['BUILDERS']['markdown'] = mdBuilder
+
 
 vars = Variables()
 vars.Add("version", "The version of this build", buildVars.addon_info["addon_version"])
@@ -75,27 +80,38 @@ buildVars.addon_info["addon_updateChannel"] = env["addon_updateChannel"]
 
 addonFile = env.File("${addon_name}-${addon_version}.nvda-addon")
 
+
 def addonGenerator(target, source, env, for_signature):
-	action = env.Action(lambda target, source, env : createAddonBundleFromPath(source[0].abspath, target[0].abspath) and None,
-	lambda target, source, env : "Generating Addon %s" % target[0])
+	action = env.Action(
+		lambda target, source, env: createAddonBundleFromPath(source[0].abspath, target[0].abspath) and None,
+		lambda target, source, env: "Generating Addon %s" % target[0]
+	)
 	return action
 
+
 def manifestGenerator(target, source, env, for_signature):
-	action = env.Action(lambda target, source, env : generateManifest(source[0].abspath, target[0].abspath) and None,
-	lambda target, source, env : "Generating manifest %s" % target[0])
+	action = env.Action(
+		lambda target, source, env: generateManifest(source[0].abspath, target[0].abspath) and None,
+		lambda target, source, env: "Generating manifest %s" % target[0]
+	)
 	return action
 
+
 def translatedManifestGenerator(target, source, env, for_signature):
 	dir = os.path.abspath(os.path.join(os.path.dirname(str(source[0])), ".."))
 	lang = os.path.basename(dir)
-	action = env.Action(lambda target, source, env : generateTranslatedManifest(source[1].abspath, lang, target[0].abspath) and None,
-	lambda target, source, env : "Generating translated manifest %s" % target[0])
+	action = env.Action(
+		lambda target, source, env: generateTranslatedManifest(source[1].abspath, lang, target[0].abspath) and None,
+		lambda target, source, env: "Generating translated manifest %s" % target[0]
+	)
 	return action
 
+
 env['BUILDERS']['NVDAAddon'] = Builder(generator=addonGenerator)
 env['BUILDERS']['NVDAManifest'] = Builder(generator=manifestGenerator)
 env['BUILDERS']['NVDATranslatedManifest'] = Builder(generator=translatedManifestGenerator)
 
+
 def createAddonHelp(dir):
 	docsDir = os.path.join(dir, "doc")
 	if os.path.isfile("style.css"):
@@ -107,6 +123,7 @@ def createAddonHelp(dir):
 		readmeTarget = env.Command(readmePath, "readme.md", Copy("$TARGET", "$SOURCE"))
 		env.Depends(addon, readmeTarget)
 
+
 def createAddonBundleFromPath(path, dest):
 	""" Creates a bundle from a directory that contains an addon manifest file."""
 	basedir = os.path.abspath(path)
@@ -117,9 +134,11 @@ def createAddonBundleFromPath(path, dest):
 			for filename in filenames:
 				pathInBundle = os.path.join(relativePath, filename)
 				absPath = os.path.join(dir, filename)
-				if pathInBundle not in buildVars.excludedFiles: z.write(absPath, pathInBundle)
+				if pathInBundle not in buildVars.excludedFiles:
+					z.write(absPath, pathInBundle)
 	return dest
 
+
 def generateManifest(source, dest):
 	addon_info = buildVars.addon_info
 	with codecs.open(source, "r", "utf-8") as f:
@@ -128,6 +147,7 @@ def generateManifest(source, dest):
 	with codecs.open(dest, "w", "utf-8") as f:
 		f.write(manifest)
 
+
 def generateTranslatedManifest(source, language, out):
 	# No ugettext in Python 3.
 	if sys.version_info.major == 2:
@@ -143,19 +163,24 @@ def generateTranslatedManifest(source, language, out):
 	with codecs.open(out, "w", "utf-8") as f:
 		f.write(result)
 
+
 def expandGlobs(files):
 	return [f for pattern in files for f in env.Glob(pattern)]
 
+
 addon = env.NVDAAddon(addonFile, env.Dir('addon'))
 
 langDirs = [f for f in env.Glob(os.path.join("addon", "locale", "*"))]
 
-#Allow all NVDA's gettext po files to be compiled in source/locale, and manifest files to be generated
+# Allow all NVDA's gettext po files to be compiled in source/locale, and manifest files to be generated
 for dir in langDirs:
 	poFile = dir.File(os.path.join("LC_MESSAGES", "nvda.po"))
-	moFile=env.gettextMoFile(poFile)
+	moFile = env.gettextMoFile(poFile)
 	env.Depends(moFile, poFile)
-	translatedManifest = env.NVDATranslatedManifest(dir.File("manifest.ini"), [moFile, os.path.join("manifest-translated.ini.tpl")])
+	translatedManifest = env.NVDATranslatedManifest(
+		dir.File("manifest.ini"),
+		[moFile, os.path.join("manifest-translated.ini.tpl")]
+	)
 	env.Depends(translatedManifest, ["buildVars.py"])
 	env.Depends(addon, [translatedManifest, moFile])
 
@@ -163,8 +188,9 @@ pythonFiles = expandGlobs(buildVars.pythonSources)
 for file in pythonFiles:
 	env.Depends(addon, file)
 
-#Convert markdown files to html
-createAddonHelp("addon") # We need at least doc in English and should enable the Help button for the add-on in Add-ons Manager
+# Convert markdown files to html
+# We need at least doc in English and should enable the Help button for the add-on in Add-ons Manager
+createAddonHelp("addon")
 for mdFile in env.Glob(os.path.join('addon', 'doc', '*', '*.md')):
 	htmlFile = env.markdown(mdFile)
 	env.Depends(htmlFile, mdFile)
@@ -172,11 +198,11 @@ for mdFile in env.Glob(os.path.join('addon', 'doc', '*', '*.md')):
 
 # Pot target
 i18nFiles = expandGlobs(buildVars.i18nSources)
-gettextvars={
-		'gettext_package_bugs_address' : 'nvda-translations@groups.io',
-		'gettext_package_name' : buildVars.addon_info['addon_name'],
-		'gettext_package_version' : buildVars.addon_info['addon_version']
-	}
+gettextvars = {
+	'gettext_package_bugs_address': 'nvda-translations@groups.io',
+	'gettext_package_name': buildVars.addon_info['addon_name'],
+	'gettext_package_version': buildVars.addon_info['addon_version']
+}
 
 pot = env.gettextPotFile("${addon_name}.pot", i18nFiles, **gettextvars)
 env.Alias('pot', pot)
@@ -192,4 +218,4 @@ env.Depends(manifest, "buildVars.py")
 
 env.Depends(addon, manifest)
 env.Default(addon)
-env.Clean (addon, ['.sconsign.dblite', 'addon/doc/en/'])
+env.Clean(addon, ['.sconsign.dblite', 'addon/doc/en/'])
diff --git a/site_scons/site_tools/gettexttool/__init__.py b/site_scons/site_tools/gettexttool/__init__.py
index 46358ca..db9a009 100644
--- a/site_scons/site_tools/gettexttool/__init__.py
+++ b/site_scons/site_tools/gettexttool/__init__.py
@@ -47,6 +47,9 @@ def generate(env):
 		suffix=".pot")
 
 	env['BUILDERS']['gettextMergePotFile'] = env.Builder(
-		action=Action("xgettext " + "--omit-header --no-location " + XGETTEXT_COMMON_ARGS,
-			"Generating pot file $TARGET"),
-		suffix=".pot")
+		action=Action(
+			"xgettext " + "--omit-header --no-location " + XGETTEXT_COMMON_ARGS,
+			"Generating pot file $TARGET"
+		),
+		suffix=".pot"
+	)