diff --git a/cirq-core/cirq/protocols/pow_protocol.py b/cirq-core/cirq/protocols/pow_protocol.py
index cc6673781c2..411fd72be64 100644
--- a/cirq-core/cirq/protocols/pow_protocol.py
+++ b/cirq-core/cirq/protocols/pow_protocol.py
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from typing import Any, overload, TYPE_CHECKING, TypeVar, Union
+from typing import Any, cast, overload, TYPE_CHECKING, TypeVar, Union, Callable
 
 if TYPE_CHECKING:
     import cirq
@@ -81,7 +81,7 @@ def pow(val: Any, exponent: Any, default: Any = RaiseTypeErrorIfNotProvided) ->
         TypeError: `val` doesn't have a __pow__ method (or that method returned
             NotImplemented) and no `default` value was specified.
     """
-    raiser = getattr(val, '__pow__', None)
+    raiser = cast(Union[None, Callable], getattr(val, '__pow__', None))
     result = NotImplemented if raiser is None else raiser(exponent)
     if result is not NotImplemented:
         return result
diff --git a/dev_tools/requirements/deps/format.txt b/dev_tools/requirements/deps/format.txt
index 27782b46137..b544c85dc39 100644
--- a/dev_tools/requirements/deps/format.txt
+++ b/dev_tools/requirements/deps/format.txt
@@ -1,2 +1,3 @@
 -r flynt.txt
 black==21.12b0
+click<=8.0.4