diff --git a/drudge/canonpy.cpp b/drudge/canonpy.cpp
index f6489f3..4d30b64 100644
--- a/drudge/canonpy.cpp
+++ b/drudge/canonpy.cpp
@@ -317,7 +317,7 @@ static PyObject* perm_repr(Perm_object* self)
     // This is used for empty or non-empty permutation.
     repr += L')';
 
-    return PyUnicode_FromUnicode(repr.data(), repr.size());
+    return PyUnicode_FromWideChar(repr.data(), repr.size());
 }
 
 /** Creates a new Perm object.
diff --git a/drudge/utils.py b/drudge/utils.py
index ac489e3..10507a1 100644
--- a/drudge/utils.py
+++ b/drudge/utils.py
@@ -11,7 +11,6 @@
     sympify, Symbol, Expr, SympifyError, count_ops, default_sort_key,
     AtomicExpr, Integer, S
 )
-from sympy.core.assumptions import ManagedProperties
 from sympy.core.sympify import CantSympify
 
 
@@ -89,7 +88,7 @@ def __call__(self, *args, **kwargs):
         return self._func(*args, **kwargs)
 
 
-class _EnumSymbsMeta(ManagedProperties):
+class _EnumSymbsMeta(type):
     """The meta class for enumeration symbols.
 
     The primary purpose of this metaclass is to set the concrete singleton