Revert "Remove importlib-metadata and importlib-resources"

This reverts commit 38435ae81c.

lib/importlib_metadata/_meta.py

@@ -0,0 +1,49 @@
+from ._compat import Protocol
+from typing import Any, Dict, Iterator, List, TypeVar, Union
+
+
+_T = TypeVar("_T")
+
+
+class PackageMetadata(Protocol):
+    def __len__(self) -> int:
+        ...  # pragma: no cover
+
+    def __contains__(self, item: str) -> bool:
+        ...  # pragma: no cover
+
+    def __getitem__(self, key: str) -> str:
+        ...  # pragma: no cover
+
+    def __iter__(self) -> Iterator[str]:
+        ...  # pragma: no cover
+
+    def get_all(self, name: str, failobj: _T = ...) -> Union[List[Any], _T]:
+        """
+        Return all values associated with a possibly multi-valued key.
+        """
+
+    @property
+    def json(self) -> Dict[str, Union[str, List[str]]]:
+        """
+        A JSON-compatible form of the metadata.
+        """
+
+
+class SimplePath(Protocol[_T]):
+    """
+    A minimal subset of pathlib.Path required by PathDistribution.
+    """
+
+    def joinpath(self) -> _T:
+        ...  # pragma: no cover
+
+    def __truediv__(self, other: Union[str, _T]) -> _T:
+        ...  # pragma: no cover
+
+    @property
+    def parent(self) -> _T:
+        ...  # pragma: no cover
+
+    def read_text(self) -> str:
+        ...  # pragma: no cover