Redefine xrange for Python 3

* Replace xrange() with range()

Author: Shuolongbj

repeat_copy.py

@@ -86,15 +86,15 @@ def _readable(datum):
   obs_batch = data.observations
   targ_batch = data.target
 
-  iterate_over = xrange(batch_size) if whole_batch else xrange(1)
+  iterate_over = range(batch_size) if whole_batch else range(1)
 
   batch_strings = []
   for batch_index in iterate_over:
     obs = obs_batch[:, batch_index, :]
     targ = targ_batch[:, batch_index, :]
 
-    obs_channels = xrange(obs.shape[1])
-    targ_channels = xrange(targ.shape[1])
+    obs_channels = range(obs.shape[1])
+    targ_channels = range(targ.shape[1])
     obs_channel_strings = [_readable(obs[:, i]) for i in obs_channels]
     targ_channel_strings = [_readable(targ[:, i]) for i in targ_channels]
 

train.py

@@ -144,7 +144,7 @@ def train(num_training_iterations, report_interval):
     start_iteration = sess.run(global_step)
     total_loss = 0
 
-    for train_iteration in xrange(start_iteration, num_training_iterations):
+    for train_iteration in range(start_iteration, num_training_iterations):
       _, loss = sess.run([train_step, train_loss])
       total_loss += loss