Replace items() with six.moves.iteritems() to improve memory usage

python/paddle/dataset/imdb.py

@@ -47,7 +47,8 @@ def tokenize(pattern):
         while tf != None:
             if bool(pattern.match(tf.name)):
                 # newline and punctuations removal and ad-hoc tokenization.
-                yield tarf.extractfile(tf).read().rstrip(six.b("\n\r")).translate(
+                yield tarf.extractfile(tf).read().rstrip(six.b(
+                    "\n\r")).translate(
                         None, six.b(string.punctuation)).lower().split()
             tf = tarf.next()
 
@@ -63,7 +64,7 @@ def build_dict(pattern, cutoff):
             word_freq[word] += 1
 
     # Not sure if we should prune less-frequent words here.
-    word_freq = [x for x in list(word_freq.items()) if x[1] > cutoff]
+    word_freq = [x for x in six.moves.iteritems(word_freq) if x[1] > cutoff]
 
     dictionary = sorted(word_freq, key=lambda x: (-x[1], x[0]))
     words, _ = list(zip(*dictionary))

python/paddle/dataset/imikolov.py

@@ -21,7 +21,7 @@ into paddle reader creators.
 import paddle.dataset.common
 import collections
 import tarfile
-from six.moves import range
+import six
 
 __all__ = ['train', 'test', 'build_dict', 'convert']
 
@@ -65,11 +65,13 @@ def build_dict(min_word_freq=50):
             # remove <unk> for now, since we will set it as last index
             del word_freq['<unk>']
 
-        word_freq = [x for x in list(word_freq.items()) if x[1] > min_word_freq]
+        word_freq = [
+            x for x in six.moves.iteritems(word_freq) if x[1] > min_word_freq
+        ]
 
         word_freq_sorted = sorted(word_freq, key=lambda x: (-x[1], x[0]))
         words, _ = list(zip(*word_freq_sorted))
-        word_idx = dict(list(zip(words, range(len(words)))))
+        word_idx = dict(list(zip(words, six.moves.range(len(words)))))
         word_idx['<unk>'] = len(words)
 
     return word_idx
@@ -90,7 +92,7 @@ def reader_creator(filename, word_idx, n, data_type):
                     l = ['<s>'] + l.strip().split() + ['<e>']
                     if len(l) >= n:
                         l = [word_idx.get(w, UNK) for w in l]
-                        for i in range(n, len(l) + 1):
+                        for i in six.moves.range(n, len(l) + 1):
                             yield tuple(l[i - n:i])
                 elif DataType.SEQ == data_type:
                     l = l.strip().split()

python/paddle/dataset/sentiment.py

@@ -20,6 +20,7 @@ The script fetch and preprocess movie_reviews data set that provided by NLTK
 TODO(yuyang18): Complete dataset.
 """
 
+import six
 import collections
 from itertools import chain
 
@@ -64,7 +65,7 @@ def get_word_dict():
         for field in movie_reviews.fileids(category):
             for words in movie_reviews.words(field):
                 word_freq_dict[words] += 1
-    words_sort_list = list(word_freq_dict.items())
+    words_sort_list = six.moves.iteritems(word_freq_dict)
     words_sort_list.sort(cmp=lambda a, b: b[1] - a[1])
     for index, word in enumerate(words_sort_list):
         words_freq_sorted.append((word[0], index))

python/paddle/dataset/wmt14.py

@@ -156,8 +156,8 @@ def get_dict(dict_size, reverse=True):
     tar_file = paddle.dataset.common.download(URL_TRAIN, 'wmt14', MD5_TRAIN)
     src_dict, trg_dict = __read_to_dict(tar_file, dict_size)
     if reverse:
-        src_dict = {v: k for k, v in list(src_dict.items())}
-        trg_dict = {v: k for k, v in list(trg_dict.items())}
+        src_dict = {v: k for k, v in six.moves.iteritems(src_dict)}
+        trg_dict = {v: k for k, v in six.moves.iteritems(trg_dict)}
     return src_dict, trg_dict
 
 

python/paddle/dataset/wmt16.py

@@ -72,7 +72,7 @@ def __build_dict(tar_file, dict_size, save_path, lang):
         fout.write("%s\n%s\n%s\n" % (START_MARK, END_MARK, UNK_MARK))
         for idx, word in enumerate(
                 sorted(
-                    iter(list(word_dict.items())),
+                    six.moves.iteritems(word_dict),
                     key=lambda x: x[1],
                     reverse=True)):
             if idx + 3 == dict_size: break

python/paddle/fluid/backward.py

@@ -46,13 +46,13 @@ def _create_op_desc_(op_type, inputs, outputs, attrs):
     """
     op_desc = core.OpDesc()
     op_desc.set_type(op_type)
-    for para, args in list(inputs.items()):
+    for para, args in six.moves.iteritems(inputs):
         op_desc.set_input(
             para,
             list(
                 map(lambda arg: arg.decode() if isinstance(arg, six.binary_type) else arg,
                     args)))
-    for para, args in list(outputs.items()):
+    for para, args in six.moves.iteritems(outputs):
         op_desc.set_output(
             para,
             list(
@@ -64,7 +64,7 @@ def _create_op_desc_(op_type, inputs, outputs, attrs):
     if op_role_attr_name not in attrs:
         attrs[
             op_role_attr_name] = core.op_proto_and_checker_maker.OpRole.Backward
-    for name, val in list(attrs.items()):
+    for name, val in six.moves.iteritems(attrs):
         if isinstance(val, framework.Block):
             op_desc.set_block_attr(name, val.desc)
         else:
@@ -187,7 +187,7 @@ def _addup_repetitive_outputs_(op_descs):
                     op_desc.set_output(param_name, arg_names)
                     renamed_vars[var_name].append(new_name)
 
-    for var_name, inputs in list(renamed_vars.items()):
+    for var_name, inputs in six.moves.iteritems(renamed_vars):
         if len(inputs) > 1:
             pending_sum_ops.append(
                 (_create_op_desc_("sum", {"X": inputs}, {"Out": [var_name]},
@@ -445,7 +445,7 @@ def _rename_grad_(block, start_op_idx, grad_to_var, target_grad_map):
                 op_desc.rename_output(name, new_name)
                 var_map[name] = new_name
 
-    for g, ng in list(var_map.items()):
+    for g, ng in six.moves.iteritems(var_map):
         if g in grad_to_var:
             grad_to_var[ng] = grad_to_var[g]
             grad_to_var.pop(g)

python/paddle/fluid/framework.py

@@ -958,7 +958,7 @@ class Block(object):
         return list(self.iter_parameters())
 
     def iter_parameters(self):
-        return (item[1] for item in list(self.vars.items())
+        return (item[1] for item in six.moves.iteritems(self.vars)
                 if isinstance(item[1], Parameter))
 
     def create_var(self, *args, **kwargs):

python/paddle/fluid/graphviz.py

@@ -106,7 +106,7 @@ class Graph(object):
 
     def _rank_repr(self):
         ranks = sorted(
-            list(self.rank_groups.items()),
+            six.moves.iteritems(self.rank_groups),
             key=functools.cmp_to_key(
                 lambda a, b: a[1].priority > b[1].priority))
         repr = []
@@ -150,8 +150,9 @@ class Node(object):
         reprs = '{name} [label={label} {extra} ];'.format(
             name=self.name,
             label=self.label,
-            extra=',' + ','.join("%s=%s" % (key, crepr(value))
-                                 for key, value in list(self.attrs.items()))
+            extra=',' + ','.join(
+                "%s=%s" % (key, crepr(value))
+                for key, value in six.moves.iteritems(self.attrs))
             if self.attrs else "")
         return reprs
 
@@ -175,7 +176,7 @@ class Edge(object):
             target=self.target.name,
             extra="" if not self.attrs else
             "[" + ','.join("{}={}".format(attr[0], crepr(attr[1]))
-                           for attr in list(self.attrs.items())) + "]")
+                           for attr in six.moves.iteritems(self.attrs)) + "]")
         return repr
 
 

python/paddle/fluid/layers/control_flow.py

@@ -22,6 +22,7 @@ from ..initializer import force_init_on_cpu
 from .ops import logical_and, logical_not, logical_or
 import numpy
 import warnings
+import six
 from functools import reduce
 
 __all__ = [
@@ -602,7 +603,7 @@ class StaticRNN(object):
         boot_memories = []
         pre_memories = []
         memories = []
-        for _, mem in list(self.memories.items()):
+        for _, mem in six.moves.iteritems(self.memories):
             boot_memories.append(mem.init)
             pre_memories.append(mem.pre_mem.name)
             mem_var = rnn_block.var(mem.mem.name)

python/paddle/fluid/metrics.py

@@ -19,6 +19,7 @@ The metrics are accomplished via Python natively.
 import numpy as np
 import copy
 import warnings
+import six
 
 __all__ = [
     'MetricBase',
@@ -79,10 +80,10 @@ class MetricBase(object):
         """
         states = {
             attr: value
-            for attr, value in list(self.__dict__.items())
+            for attr, value in six.moves.iteritems(self.__dict__)
             if not attr.startswith("_")
         }
-        for attr, value in list(states.items()):
+        for attr, value in six.moves.iteritems(states):
             if isinstance(value, int):
                 setattr(self, attr, 0)
             elif isinstance(value, float):
@@ -105,7 +106,7 @@ class MetricBase(object):
         """
         states = {
             attr: value
-            for attr, value in list(self.__dict__.items())
+            for attr, value in six.moves.iteritems(self.__dict__)
             if not attr.startswith("_")
         }
         config = {}

python/paddle/fluid/tests/unittests/benchmark.py

@@ -54,7 +54,7 @@ class BenchmarkSuite(OpTest):
 
     def _get_input_names(self):
         inputs = []
-        for name, value in list(self.inputs.items()):
+        for name, value in six.moves.iteritems(self.inputs):
             if isinstance(value, list):
                 inputs.extend([sub_name for sub_name, _ in value])
             inputs.append(name)
@@ -62,7 +62,7 @@ class BenchmarkSuite(OpTest):
 
     def _get_output_names(self):
         outputs = []
-        for var_name, var in list(self.outputs.items()):
+        for var_name, var in six.moves.iteritems(self.outputs):
             if isinstance(var, list):
                 for sub_var_name, sub_var in var:
                     outputs.append(sub_var_name)

python/paddle/fluid/tests/unittests/test_detection_map_op.py

@@ -14,6 +14,7 @@
 
 import unittest
 import numpy as np
+import six
 import sys
 import collections
 import math
@@ -176,7 +177,7 @@ class TestDetectionMAPOp(OpTest):
             true_pos[label].append([score, tp])
             false_pos[label].append([score, fp])
 
-        for (label, label_pos_num) in list(label_count.items()):
+        for (label, label_pos_num) in six.moves.iteritems(label_count):
             if label_pos_num == 0 or label not in true_pos: continue
             label_true_pos = true_pos[label]
             label_false_pos = false_pos[label]

python/paddle/fluid/tests/unittests/test_lod_rank_table.py

@@ -18,6 +18,7 @@ from paddle.fluid.executor import Executor
 import paddle.fluid.core as core
 import numpy
 import unittest
+import six
 
 
 class TestLoDRankTable(unittest.TestCase):
@@ -36,7 +37,7 @@ class TestLoDRankTable(unittest.TestCase):
         exe.run(scope=scope, feed={'x': tensor})
         var = scope.find_var(rank_table.name)
         table = var.get_lod_rank_table()
-        self.assertEqual([(0, 5), (1, 1), (2, 1)], list(table.items()))
+        self.assertEqual([(0, 5), (1, 1), (2, 1)], six.moves.iteritems(table))
 
 
 if __name__ == '__main__':

python/paddle/fluid/tests/unittests/test_positive_negative_pair_op.py

@@ -15,6 +15,7 @@
 import unittest
 import itertools
 import numpy as np
+import six
 from op_test import OpTest
 
 
@@ -32,7 +33,7 @@ def py_pnpair_op(score, label, query, column=-1, weight=None):
 
     # accumulate statistics
     pos, neg, neu = 0, 0, 0
-    for _, ranks in list(predictions.items()):
+    for _, ranks in six.moves.iteritems(predictions):
         for e1, e2 in itertools.combinations(ranks, 2):
             s1, s2, l1, l2, w1, w2 = e1[0], e2[0], e1[1], e2[1], e1[2], e2[2]
             w = (w1 + w2) * 0.5

python/paddle/fluid/trainer.py

@@ -16,6 +16,7 @@ import contextlib
 import os
 import errno
 import shutil
+import six
 import time
 
 from . import core
@@ -618,7 +619,7 @@ def build_feed_var_list(program, feed_order):
                 "The values of 'feed_order' should be a permutation of [0, len(feed_order))"
             )
         sorted_pair_list = sorted(
-            list(feed_order.items()), key=lambda item: item[1])
+            six.moves.iteritems(feed_order), key=lambda item: item[1])
         feed_var_list = [
             program.global_block().var(pair[0]) for pair in sorted_pair_list
         ]
@@ -1036,7 +1037,7 @@ def _save_trainer_args(dirname, trainer_id, trainer_args):
 
     cur_dir = _get_trainer_dir(dirname, trainer_id)
 
-    for name, value in list(trainer_args.items()):
+    for name, value in six.moves.iteritems(trainer_args):
         args_file = os.path.join(cur_dir, name)
         with open(args_file, 'w') as f:
             f.write(str(value))

python/paddle/fluid/transpiler/distribute_transpiler.py

@@ -218,7 +218,8 @@ class DistributeTranspiler(object):
         #       fc_w@GRAD_trainer_0, fc_w@GRAD_trainer_1 --> pserver1
         #       fc_b@GRAD_trainer_0, fc_b@GRAD_trainer_1 --> pserver2
         # shuffle the map will avoid the uneven distribution above
-        grad_var_mapping_items = list(self.grad_var_mapping.items())
+        grad_var_mapping_items = list(
+            six.moves.iteritems(self.grad_var_mapping))
 
         if not self.config.slice_var_up:
             random.seed(self.origin_program.random_seed)
@@ -279,7 +280,7 @@ class DistributeTranspiler(object):
             self.param_grad_ep_mapping[ep]["grads"].append(send_vars[i])
 
         # step4: Concat the parameters splits together after recv.
-        for varname, splited_var in list(self.param_var_mapping.items()):
+        for varname, splited_var in six.moves.iteritems(self.param_var_mapping):
             eps = []
             for var in splited_var:
                 index = [v.name for v in recv_vars].index(var.name)
@@ -303,7 +304,7 @@ class DistributeTranspiler(object):
                 RPC_OP_ROLE_ATTR_NAME: RPC_OP_ROLE_ATTR_VALUE
             })
 
-        for varname, splited_var in list(self.param_var_mapping.items()):
+        for varname, splited_var in six.moves.iteritems(self.param_var_mapping):
             if len(splited_var) <= 1:
                 continue
             orig_param = program.global_block().vars[varname]
@@ -560,7 +561,7 @@ class DistributeTranspiler(object):
         # 1. create vars in pserver program to startup program
         pserver_vars = pserver_program.global_block().vars
         created_var_map = collections.OrderedDict()
-        for _, var in list(pserver_vars.items()):
+        for _, var in six.moves.iteritems(pserver_vars):
             tmpvar = s_prog.global_block()._clone_variable(var)
             created_var_map[var.name] = tmpvar
 
@@ -997,7 +998,7 @@ class DistributeTranspiler(object):
                 block_map[varname] = []
             block_map[varname].append((int(offset), int(size)))
 
-        for varname, splited in list(block_map.items()):
+        for varname, splited in six.moves.iteritems(block_map):
             orig_var = program.global_block().var(varname)
             if len(splited) == 1:
                 if self.sync_mode and add_trainer_suffix:
@@ -1248,9 +1249,7 @@ class DistributeTranspiler(object):
 
     def _is_splited_grad_var(self, var, var_dict):
         grad_block = None
-        # TODO(minqiyang): replace these items() with six.iteritems() to
-        # improve memory
-        for _, g in list(var_dict.items()):
+        for _, g in six.moves.iteritems(var_dict):
             if self._orig_varname(g.name) == self._orig_varname(var.name):
                 if g.name.find(".trainer_") == -1:
                     grad_block = g
@@ -1260,7 +1259,7 @@ class DistributeTranspiler(object):
     def _clone_lr_op(self, program, block, op):
         inputs = self._get_input_map_from_op(
             self.origin_program.global_block().vars, op)
-        for key, varlist in list(inputs.items()):
+        for key, varlist in six.moves.iteritems(inputs):
             if not isinstance(varlist, list):
                 varlist = [varlist]
             for var in varlist:
@@ -1269,7 +1268,7 @@ class DistributeTranspiler(object):
 
         outputs = self._get_output_map_from_op(
             self.origin_program.global_block().vars, op)
-        for key, varlist in list(outputs.items()):
+        for key, varlist in six.moves.iteritems(outputs):
             if not isinstance(varlist, list):
                 varlist = [varlist]
             for var in varlist:
@@ -1284,7 +1283,7 @@ class DistributeTranspiler(object):
         # Append the ops for parameters that do not need to be optimized/updated
         inputs = self._get_input_map_from_op(
             self.origin_program.global_block().vars, opt_op)
-        for key, varlist in list(inputs.items()):
+        for key, varlist in six.moves.iteritems(inputs):
             if not isinstance(varlist, list):
                 varlist = [varlist]
             for var in varlist:
@@ -1303,7 +1302,7 @@ class DistributeTranspiler(object):
 
         outputs = self._get_output_map_from_op(
             self.origin_program.global_block().vars, opt_op)
-        for key, varlist in list(outputs.items()):
+        for key, varlist in six.moves.iteritems(outputs):
             if not isinstance(varlist, list):
                 varlist = [varlist]
             for var in varlist: