Fix importlib.resources for mypy (#2130)

stdlib/3.7/importlib/resources.pyi

@@ -1,22 +0,0 @@
-import os
-
-from pathlib import Path
-from types import ModuleType
-from typing import ContextManager, Iterator, Union, BinaryIO, TextIO
-
-Package = Union[str, ModuleType]
-Resource = Union[str, os.PathLike]
-
-def open_binary(package: Package, resource: Resource) -> BinaryIO: ...
-def open_text(package: Package,
-              resource: Resource,
-              encoding: str = ...,
-              errors: str = ...) -> TextIO: ...
-def read_binary(package: Package, resource: Resource) -> bytes: ...
-def read_text(package: Package,
-              resource: Resource,
-              encoding: str = ...,
-              errors: str = ...) -> str: ...
-def path(package: Package, resource: Resource) -> ContextManager[Path]: ...
-def is_resource(package: Package, name: str) -> bool: ...
-def contents(package: Package) -> Iterator[str]: ...

stdlib/3/importlib/resources.pyi

@@ -0,0 +1,25 @@
+import sys
+# This is a >=3.7 module, so we conditionally include its source.
+if sys.version_info >= (3, 7):
+    import os
+
+    from pathlib import Path
+    from types import ModuleType
+    from typing import ContextManager, Iterator, Union, BinaryIO, TextIO
+
+    Package = Union[str, ModuleType]
+    Resource = Union[str, os.PathLike]
+
+    def open_binary(package: Package, resource: Resource) -> BinaryIO: ...
+    def open_text(package: Package,
+                resource: Resource,
+                encoding: str = ...,
+                errors: str = ...) -> TextIO: ...
+    def read_binary(package: Package, resource: Resource) -> bytes: ...
+    def read_text(package: Package,
+                resource: Resource,
+                encoding: str = ...,
+                errors: str = ...) -> str: ...
+    def path(package: Package, resource: Resource) -> ContextManager[Path]: ...
+    def is_resource(package: Package, name: str) -> bool: ...
+    def contents(package: Package) -> Iterator[str]: ...