Single file modules

Author: m-novikov

Diff for: mypy/build.py

@@ -859,9 +859,11 @@ def find_modules_recursive(module: str, lib_path: List[str]) -> List[BuildSource
 
 def verify_module(id: str, path: str) -> bool:
     """Check that all packages containing id have a __init__ file."""
+    if path.endswith(tuple(PYTHON_EXTENSIONS)):
+        return True
+
     if path.endswith(('__init__.py', '__init__.pyi')):
         path = dirname(path)
-        return True
 
     for i in range(id.count('.')):
         path = dirname(path)