lint + docstring

Author: radix

effect/test_fold.py

@@ -63,15 +63,15 @@ def test_fold_effect_errors():
     assert excinfo.value.wrapped_exception[0] is ZeroDivisionError
     assert str(excinfo.value.wrapped_exception[1]) == 'foo'
 
+
 def test_fold_effect_str():
+    """str()ing a FoldError returns useful traceback/exception info."""
     effs = [Effect('a'), Effect(Error(ZeroDivisionError('foo'))), Effect('c')]
-
     dispatcher = SequenceDispatcher([
         ('a', lambda i: 'Ei'),
     ])
 
     eff = fold_effect(operator.add, 'Nil', effs)
-
     with dispatcher.consume():
         with raises(FoldError) as excinfo:
             sync_perform(_base_and(dispatcher), eff)