[build] Add python_library for mako

Change-Id: Ifea35ea4be281f8ff9b46ef550194062ff6fc76a
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/mako/+/515688
Reviewed-by: Shai Barack <shayba@google.com>
diff --git a/BUILD.gn b/BUILD.gn
new file mode 100644
index 0000000..920bc88
--- /dev/null
+++ b/BUILD.gn
@@ -0,0 +1,37 @@
+# Copyright 2021 The Fuchsia Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//build/python/python_library.gni")
+
+python_library("mako") {
+  source_root = "mako"
+  sources = [
+    "__init__.py",
+    "_ast_util.py",
+    "ast.py",
+    "cache.py",
+    "cmd.py",
+    "codegen.py",
+    "compat.py",
+    "exceptions.py",
+    "ext/__init__.py",
+    "ext/autohandler.py",
+    "ext/babelplugin.py",
+    "ext/beaker_cache.py",
+    "ext/extract.py",
+    "ext/linguaplugin.py",
+    "ext/preprocessors.py",
+    "ext/pygmentplugin.py",
+    "ext/turbogears.py",
+    "filters.py",
+    "lexer.py",
+    "lookup.py",
+    "parsetree.py",
+    "pygen.py",
+    "pyparser.py",
+    "runtime.py",
+    "template.py",
+    "util.py",
+  ]
+}
diff --git a/README.fuchsia b/README.fuchsia
index ccf53ee..7761462 100644
--- a/README.fuchsia
+++ b/README.fuchsia
@@ -12,3 +12,4 @@
 Local Modifications:
 Added README.fuchsia.
 Added py_srcs.gni.
+Added BUILD.gn.