Make mypy pre-commit pass (#5850)

* Make mypy pre-commit pass

Author: max-sixty

.pre-commit-config.yaml

@@ -33,17 +33,18 @@ repos:
     rev: v0.910-1
     hooks:
       - id: mypy
-        # Copied from setup.cfg
-        exclude: "properties|asv_bench"
+        # `properies` & `asv_bench` are copied from setup.cfg.
+        # `_typed_ops.py` is added since otherwise mypy will complain (but notably only in pre-commit)
+        exclude: "properties|asv_bench|_typed_ops.py"
         additional_dependencies: [
             # Type stubs
             types-python-dateutil,
             types-pkg_resources,
             types-PyYAML,
             types-pytz,
+            typing-extensions==3.10.0.0,
             # Dependencies that are typed
             numpy,
-            typing-extensions==3.10.0.0,
           ]
   # run this occasionally, ref discussion https://github.com/pydata/xarray/pull/3194
   # - repo: https://github.com/asottile/pyupgrade