2 files changed, 13 insertions, 8 deletions
diff --git a/pyasn1/codec/native/decoder.py b/pyasn1/codec/native/decoder.py
index 04ae129..db30c71 100644
--- a/pyasn1/codec/native/decoder.py
+++ b/pyasn1/codec/native/decoder.py
@@ -181,11 +181,13 @@ class SingleItemDecoder(object):
 
 
 class Decoder(object):
-    SINGLE_ITEM_DECODER = SingleItemDecoder()
+    SINGLE_ITEM_DECODER = SingleItemDecoder
 
-    @classmethod
-    def __call__(cls, pyObject, asn1Spec=None, **kwargs):
-        return cls.SINGLE_ITEM_DECODER(pyObject, asn1Spec=asn1Spec, **kwargs)
+    def __init__(self, **options):
+        self._singleItemDecoder = self.SINGLE_ITEM_DECODER()
+
+    def __call__(self, pyObject, asn1Spec=None, **kwargs):
+        return self._singleItemDecoder(pyObject, asn1Spec=asn1Spec, **kwargs)
 
 
 #: Turns Python objects of built-in types into ASN.1 objects.
diff --git a/pyasn1/codec/native/encoder.py b/pyasn1/codec/native/encoder.py
index 0001916..d0d65ec 100644
--- a/pyasn1/codec/native/encoder.py
+++ b/pyasn1/codec/native/encoder.py
@@ -225,11 +225,14 @@ class SingleItemEncoder(object):
 
 
 class Encoder(object):
-    SINGLE_ITEM_ENCODER = SingleItemEncoder()
+    SINGLE_ITEM_ENCODER = SingleItemEncoder
 
-    @classmethod
-    def __call__(cls, pyObject, asn1Spec=None, **kwargs):
-        return cls.SINGLE_ITEM_ENCODER(pyObject, asn1Spec=asn1Spec, **kwargs)
+    def __init__(self, **kwargs):
+        self._singleItemEncoder = self.SINGLE_ITEM_ENCODER()
+
+    def __call__(self, pyObject, asn1Spec=None, **options):
+        return self._singleItemEncoder(
+            pyObject, asn1Spec=asn1Spec, **options)
 
 
 #: Turns ASN.1 object into a Python built-in type object(s).