| Index: build/build.py | 
| diff --git a/build/build.py b/build/build.py | 
| index 2a77c847fb51a6bdda37c1ddb54909694ccf0050..c399ce8d88368eee8f315c9e2c18d3bbd190de6b 100755 | 
| --- a/build/build.py | 
| +++ b/build/build.py | 
| @@ -178,11 +178,14 @@ def read_yaml(py_venv, path): | 
| else: | 
| python_venv_path = ('bin', 'python') | 
| executable = os.path.join(py_venv, *python_venv_path) | 
| +  env = os.environ.copy() | 
| +  env.pop('PYTHONPATH', None) | 
| proc = subprocess.Popen( | 
| [executable, '-c', oneliner], | 
| executable=executable, | 
| stdin=subprocess.PIPE, | 
| -      stdout=subprocess.PIPE) | 
| +      stdout=subprocess.PIPE, | 
| +      env=env) | 
| with open(path, 'r') as f: | 
| out, _ = proc.communicate(f.read()) | 
| if proc.returncode: | 
|  |