--- /dev/null
+
+cdef class MyInt(int):
+ """
+ >>> MyInt(2) == 2
+ True
+ >>> MyInt(2).attr is None
+ True
+ """
+ cdef readonly object attr
+
+cdef class MyFloat(float):
+ """
+ >>> MyFloat(1.0)== 1.0
+ True
+ >>> MyFloat(1.0).attr is None
+ True
+ """
+ cdef readonly object attr
+
+ustring = u'abc'
+
+cdef class MyUnicode(unicode):
+ """
+ >>> MyUnicode(ustring) == ustring
+ True
+ >>> MyUnicode(ustring).attr is None
+ True
+ """
+ cdef readonly object attr
+
+cdef class MyList(list):
+ """
+ >>> MyList([1,2,3]) == [1,2,3]
+ True
+ >>> MyList([1,2,3]).attr is None
+ True
+ """
+ cdef readonly object attr
+
+cdef class MyDict(dict):
+ """
+ >>> MyDict({1:2, 3:4}) == {1:2, 3:4}
+ True
+ >>> MyDict({1:2, 3:4}).attr is None
+ True
+ """
+ cdef readonly object attr