Add stubs for _version.py

src/attr/__init__.pyi

@@ -20,6 +20,8 @@ from . import filters as filters
 from . import converters as converters
 from . import validators as validators
 
+from ._version import VersionInfo
+
 _T = TypeVar("_T")
 _C = TypeVar("_C", bound=type)
 

src/attr/_version.pyi

@@ -0,0 +1,5 @@
+class VersionInfo:
+    year: int
+    minor: int
+    micro: int
+    releaselevel: str

tox.ini

@@ -93,5 +93,5 @@ commands = towncrier --draft
 basepython = python3.7
 deps = mypy
 commands =
-    mypy src/attr/__init__.pyi src/attr/converters.pyi src/attr/exceptions.pyi src/attr/filters.pyi src/attr/validators.pyi
+    mypy src/attr/__init__.pyi src/attr/_version.pyi src/attr/converters.pyi src/attr/exceptions.pyi src/attr/filters.pyi src/attr/validators.pyi
     mypy tests/typing_example.py