Move importlib.resources to be in 3, but only usable on 3.7

Author: emmatyping

stdlib/3.7/importlib/__init__.pyi

@@ -0,0 +1,23 @@
+if system.version_info >= (3,7,0):
+    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]: ...