diff --git a/cirq/protocols/approximate_equality_protocol_test.py b/cirq/protocols/approximate_equality_protocol_test.py
index 7d8f8319143..57435be748d 100644
--- a/cirq/protocols/approximate_equality_protocol_test.py
+++ b/cirq/protocols/approximate_equality_protocol_test.py
@@ -47,11 +47,11 @@ def test_approx_eq_mixed_primitives():
 
 def test_numpy_dtype_compatibility():
     i_a, i_b, i_c = 0, 1, 2
-    i_types = [np.intc, np.intp, np.int0, np.int8, np.int16, np.int32, np.int64]
+    i_types = [np.intc, np.intp, np.int8, np.int16, np.int32, np.int64]
     for i_type in i_types:
         assert cirq.approx_eq(i_type(i_a), i_type(i_b), atol=1)
         assert not cirq.approx_eq(i_type(i_a), i_type(i_c), atol=1)
-    u_types = [np.uint, np.uint0, np.uint8, np.uint16, np.uint32, np.uint64]
+    u_types = [np.uint, np.uintp, np.uint8, np.uint16, np.uint32, np.uint64]
     for u_type in u_types:
         assert cirq.approx_eq(u_type(i_a), u_type(i_b), atol=1)
         assert not cirq.approx_eq(u_type(i_a), u_type(i_c), atol=1)
diff --git a/cirq/protocols/resolve_parameters.py b/cirq/protocols/resolve_parameters.py
index 3243f26b555..cc515f45522 100644
--- a/cirq/protocols/resolve_parameters.py
+++ b/cirq/protocols/resolve_parameters.py
@@ -178,8 +178,10 @@ def resolve_parameters(
     if isinstance(val, (list, tuple)):
         return cast(T, type(val)(resolve_parameters(e, param_resolver, recursive) for e in val))
 
-    is_parameterized = getattr(val, '_is_parameterized_', None)
-    if is_parameterized is not None and not is_parameterized():
+    is_parameterized = (
+        val._is_parameterized_() if hasattr(val, '_is_parameterized_') else NotImplemented
+    )
+    if is_parameterized is not NotImplemented and not is_parameterized:
         return val
 
     getter = getattr(val, '_resolve_parameters_', None)
diff --git a/cirq/sim/simulation_state_test.py b/cirq/sim/simulation_state_test.py
index eab1e884676..f493c1f1435 100644
--- a/cirq/sim/simulation_state_test.py
+++ b/cirq/sim/simulation_state_test.py
@@ -43,8 +43,8 @@ def _act_on_fallback_(
         return True
 
     def add_qubits(self, qubits):
-        ret = super().add_qubits(qubits)
-        return self if NotImplemented else ret
+        super().add_qubits(qubits)
+        return self
 
 
 class DelegatingAncillaZ(cirq.Gate):