diff --git a/src/openfermion/_compat.py b/src/openfermion/_compat.py
index bc90c8c98..e7527537f 100644
--- a/src/openfermion/_compat.py
+++ b/src/openfermion/_compat.py
@@ -9,12 +9,15 @@
 #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #   See the License for the specific language governing permissions and
 #   limitations under the License.
-from typing import Dict, Tuple
+
+from typing import Any, Dict, Tuple
 from types import ModuleType
 import warnings
 
 
-def wrap_module(module: ModuleType, deprecated_attributes: Dict[str, Tuple[str, str]]):
+def wrap_module(
+    module: ModuleType, deprecated_attributes: Dict[str, Tuple[str, str]]
+) -> ModuleType:
     """Wrap a module with deprecated attributes.
 
     Args:
@@ -31,7 +34,7 @@ def wrap_module(module: ModuleType, deprecated_attributes: Dict[str, Tuple[str,
     class Wrapped(ModuleType):
         __dict__ = module.__dict__
 
-        def __getattr__(self, name):
+        def __getattr__(self, name: str) -> Any:
             if name in deprecated_attributes:
                 version, fix = deprecated_attributes[name]
                 warnings.warn(
diff --git a/src/openfermion/_compat_test.py b/src/openfermion/_compat_test.py
index 68cdd4db6..a53724863 100644
--- a/src/openfermion/_compat_test.py
+++ b/src/openfermion/_compat_test.py
@@ -9,6 +9,7 @@
 #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #   See the License for the specific language governing permissions and
 #   limitations under the License.
+
 from typing import Any, Callable
 import functools
 import warnings
@@ -17,7 +18,6 @@
 import deprecation
 
 from cirq._compat import deprecated
-from cirq.testing import assert_deprecated
 
 import openfermion
 from openfermion._compat import wrap_module
@@ -36,7 +36,7 @@ def deprecated_test(test: Callable) -> Callable:
     """
 
     @functools.wraps(test)
-    def decorated_test(*args, **kwargs) -> Any:
+    def decorated_test(*args: Any, **kwargs: Any) -> Any:
         with pytest.deprecated_call():
             test(*args, **kwargs)
 
@@ -44,13 +44,13 @@ def decorated_test(*args, **kwargs) -> Any:
 
 
 @deprecation.deprecated()
-def f():
+def f() -> None:
     pass
 
 
-def test_deprecated_test():
+def test_deprecated_test() -> None:
     @deprecated_test
-    def test():
+    def test() -> None:
         f()
 
     with warnings.catch_warnings(record=True) as w:
@@ -60,16 +60,16 @@ def test():
         assert len(w) == 0
 
 
-def test_wrap_module():
-    openfermion.deprecated_attribute = None
+def test_wrap_module() -> None:
+    openfermion.deprecated_attribute = None  # type: ignore[attr-defined]
     wrapped_openfermion = wrap_module(openfermion, {'deprecated_attribute': ('', '')})
     with pytest.deprecated_call():
-        _ = wrapped_openfermion.deprecated_attribute
+        _ = wrapped_openfermion.deprecated_attribute  # type: ignore[attr-defined]
 
 
-def test_cirq_deprecations():
+def test_cirq_deprecations() -> None:
     @deprecated(deadline="v0.12", fix="use new_func")
-    def old_func():
+    def old_func() -> None:
         pass
 
     with pytest.raises(ValueError, match="deprecated .* not allowed"):
diff --git a/src/openfermion/conftest.py b/src/openfermion/conftest.py
index ff9a716d6..104edd1a1 100644
--- a/src/openfermion/conftest.py
+++ b/src/openfermion/conftest.py
@@ -12,11 +12,13 @@
 
 import os
 import random
-import pytest
+from typing import Any
+
 import numpy as np
+import pytest
 
 
-def pytest_configure(config):
+def pytest_configure(config: Any) -> None:
     # Set seeds for collection-time parameterization.
     random.seed(0)
     np.random.seed(0)
@@ -25,7 +27,7 @@ def pytest_configure(config):
 
 
 @pytest.fixture(autouse=True)
-def set_random_seed():
+def set_random_seed() -> None:
     """Set a fixed random seed when testing."""
     random.seed(0)
     np.random.seed(0)