diff --git a/python/paddle/dataset/cifar.py b/python/paddle/dataset/cifar.py
index 0e5bbfc45a8eeb40692abab456e9d961f06e5815..0d07462e684b094f35dc373fb144730fc9cc54ec 100644
--- a/python/paddle/dataset/cifar.py
+++ b/python/paddle/dataset/cifar.py
@@ -32,7 +32,7 @@ import itertools
 import numpy
 import paddle.dataset.common
 import tarfile
-from six.moves import zip
+import six
 from six.moves import cPickle as pickle
 
 __all__ = ['train100', 'test100', 'train10', 'test10', 'convert']
@@ -46,25 +46,22 @@ CIFAR100_MD5 = 'eb9058c3a382ffc7106e4002c42a8d85'
 
 def reader_creator(filename, sub_name, cycle=False):
     def read_batch(batch):
-        data = batch['data']
-        labels = batch.get('labels', batch.get('fine_labels', None))
+        data = batch[six.b('data')]
+        labels = batch.get(six.b('labels'), batch.get(six.b('fine_labels'), None))
         assert labels is not None
-        for sample, label in zip(data, labels):
+        for sample, label in six.moves.zip(data, labels):
             yield (sample / 255.0).astype(numpy.float32), int(label)
 
     def reader():
         with tarfile.open(filename, mode='r') as f:
-            names = (each_item.name for each_item in f
-                     if sub_name in each_item.name)
+            names = [each_item.name for each_item in f if sub_name in each_item.name]
 
             while True:
                 for name in names:
-                    import sys
-                    print(name)
-                    sys.stdout.flush()
-                    print(f.extractfile(name))
-                    sys.stdout.flush()
-                    batch = pickle.load(f.extractfile(name))
+                    if six.PY2:
+                        batch = pickle.load(f.extractfile(name))
+                    else:
+                        batch = pickle.load(f.extractfile(name), encoding='bytes')
                     for item in read_batch(batch):
                         yield item
                 if not cycle:
diff --git a/python/paddle/dataset/common.py b/python/paddle/dataset/common.py
index 8abb4d2790da2bae4a800ffb2f75c4748136e5bf..07e6b199c003fbd89b3f6543e0a5a2d808f9fb75 100644
--- a/python/paddle/dataset/common.py
+++ b/python/paddle/dataset/common.py
@@ -87,20 +87,14 @@ def download(url, module_name, md5sum, save_name=None):
 
         if total_length is None:
             with open(filename, 'wb') as f:
-                import sys
-                print("write follow block")
-                sys.stdout.flush()
-                shutil.copyfileobj(cpt.to_bytes(r.raw), f)
+                shutil.copyfileobj(r.raw, f)
         else:
             with open(filename, 'wb') as f:
-                import sys
-                print("write follow length")
-                sys.stdout.flush()
                 dl = 0
                 total_length = int(total_length)
                 for data in r.iter_content(chunk_size=4096):
                     dl += len(data)
-                    f.write(cpt.to_bytes(data))
+                    f.write(data)
                     done = int(50 * dl / total_length)
                     sys.stdout.write("\r[%s%s]" % ('=' * done,
                                                    ' ' * (50 - done)))
diff --git a/python/paddle/fluid/compat.py b/python/paddle/fluid/compat.py
index 05633583ccb60af22fdb9b991c352a06475d3771..fe23a5929ad42abb7606f3e953e1dd4c389c0485 100644
--- a/python/paddle/fluid/compat.py
+++ b/python/paddle/fluid/compat.py
@@ -27,7 +27,7 @@ def to_literal_str(obj):
 
 def _to_literal_str(obj):
     if isinstance(obj, six.binary_type):
-        return obj.decode('latin-1')
+        return obj.decode('utf-8')
     elif isinstance(obj, six.text_type):
         return obj
     else:
@@ -45,7 +45,7 @@ def to_bytes(obj):
 
 def _to_bytes(obj):
     if isinstance(obj, six.text_type):
-        return obj.encode('latin-1')
+        return obj.encode('utf-8')
     elif isinstance(obj, six.binary_type):
         return obj
     else:
diff --git a/python/paddle/fluid/tests/book/high-level-api/image_classification/cifar10_small_test_set.py b/python/paddle/fluid/tests/book/high-level-api/image_classification/cifar10_small_test_set.py
index e7b709f31be4df2417b0d429e43e77a68f00d63d..9afac4143e3fd8d5fdc2fe7bafbc36f58fbb470d 100644
--- a/python/paddle/fluid/tests/book/high-level-api/image_classification/cifar10_small_test_set.py
+++ b/python/paddle/fluid/tests/book/high-level-api/image_classification/cifar10_small_test_set.py
@@ -32,8 +32,8 @@ import itertools
 import numpy
 import paddle.dataset.common
 import tarfile
+import six
 from six.moves import cPickle as pickle
-from six.moves import zip
 
 __all__ = ['train10']
 
@@ -44,20 +44,23 @@ CIFAR10_MD5 = 'c58f30108f718f92721af3b95e74349a'
 
 def reader_creator(filename, sub_name, batch_size=None):
     def read_batch(batch):
-        data = batch['data']
-        labels = batch.get('labels', batch.get('fine_labels', None))
+        data = batch[six.b('data')]
+        labels = batch.get(six.b('labels'), batch.get(six.b('fine_labels'), None))
         assert labels is not None
-        for sample, label in zip(data, labels):
+        for sample, label in six.moves.zip(data, labels):
             yield (sample / 255.0).astype(numpy.float32), int(label)
 
     def reader():
         with tarfile.open(filename, mode='r') as f:
-            names = (each_item.name for each_item in f
-                     if sub_name in each_item.name)
+            names = [each_item.name for each_item in f
+                     if sub_name in each_item.name]
 
             batch_count = 0
             for name in names:
-                batch = pickle.load(f.extractfile(name))
+                if six.PY2:
+                    batch = pickle.load(f.extractfile(name))
+                else:
+                    batch = pickle.load(f.extractfile(name), encoding='bytes')
                 for item in read_batch(batch):
                     if isinstance(batch_size, int) and batch_count > batch_size:
                         break