diff --git a/setup.py b/setup.py
index 3ecfa17c6dca5..3a9bc6b157c16 100644
--- a/setup.py
+++ b/setup.py
@@ -3,6 +3,7 @@
 from setuptools.command.build_py import build_py
 import subprocess
 import sys
+import os
 
 
 def run_command(command, cwd=None):
@@ -32,6 +33,9 @@ class CustomBuild(build_py):
   def run(self):
     super().run()
 
+    top_level_dir = os.path.abspath(os.path.dirname(__file__))
+    os.environ['PYTHONPATH'] = top_level_dir
+
     # Running GN to generate build files
     print('Generating build files with GN...')
     run_command(