Fix rest of flake8 error lambda functions (E731)

src/diffpy/srfit/equation/builder.py

@@ -662,13 +662,16 @@ def __wrapSrFitOperators():
     """
     opmod = literals.operators
     excluded_types = set((opmod.CustomOperator, opmod.UFuncOperator))
-    # check if opmod member should be wrapped as OperatorBuilder
-    is_exported_type = lambda cls: (
-        inspect.isclass(cls)
-        and issubclass(cls, opmod.Operator)
-        and not inspect.isabstract(cls)
-        and cls not in excluded_types
-    )
+
+    def is_exported_type(cls):
+        """Check if the class should be wrapped as OperatorBuilder."""
+        return (
+            inspect.isclass(cls) and
+            issubclass(cls, opmod.Operator) and
+            not inspect.isabstract(cls) and
+            cls not in excluded_types
+        )
+
     # create OperatorBuilder objects
     for nm, opclass in inspect.getmembers(opmod, is_exported_type):
         op = opclass()

src/diffpy/srfit/sas/prcalculator.py

@@ -92,9 +92,7 @@ def __call__(self, r):
         self._invertor.y = iq
         self._invertor.err = diq
         c, c_cov = self._invertor.invert_optimize()
-        calculate_pr = lambda x: self._invertor.pr(c, x)
-        pr = map(calculate_pr, r)
-
+        pr = map(lambda x: self._invertor.pr(c, x), r)
         pr = numpy.array(pr)
         return self.scale.value * pr
 

src/diffpy/srfit/tests/testcontribution.py

@@ -270,7 +270,7 @@ def test_releaseOldEquations(self):
     def test_registerFunction(self):
         """Ensure registered function works after second setEquation call."""
         fc = self.fitcontribution
-        fsquare = lambda x: x**2
+        fsquare = lambda x: x**2  # noqa: E731
         fc.registerFunction(fsquare, name="fsquare")
         fc.setEquation("fsquare")
         fc.x.setValue(5)