Expose layer's name for sequence pad & unpad

test=develop

paddle/fluid/API.spec

@@ -75,8 +75,8 @@ paddle.fluid.layers.conv2d_transpose ArgSpec(args=['input', 'num_filters', 'outp
 paddle.fluid.layers.conv3d_transpose ArgSpec(args=['input', 'num_filters', 'output_size', 'filter_size', 'padding', 'stride', 'dilation', 'groups', 'param_attr', 'bias_attr', 'use_cudnn', 'act', 'name'], varargs=None, keywords=None, defaults=(None, None, 0, 1, 1, None, None, None, True, None, None))
 paddle.fluid.layers.sequence_expand ArgSpec(args=['x', 'y', 'ref_level', 'name'], varargs=None, keywords=None, defaults=(-1, None))
 paddle.fluid.layers.sequence_expand_as ArgSpec(args=['x', 'y', 'name'], varargs=None, keywords=None, defaults=(None,))
-paddle.fluid.layers.sequence_pad ArgSpec(args=['x', 'pad_value', 'maxlen'], varargs=None, keywords=None, defaults=(None,))
-paddle.fluid.layers.sequence_unpad ArgSpec(args=['x', 'length'], varargs=None, keywords=None, defaults=None)
+paddle.fluid.layers.sequence_pad ArgSpec(args=['x', 'pad_value', 'maxlen', 'name'], varargs=None, keywords=None, defaults=(None, None))
+paddle.fluid.layers.sequence_unpad ArgSpec(args=['x', 'length', 'name'], varargs=None, keywords=None, defaults=(None,))
 paddle.fluid.layers.lstm_unit ArgSpec(args=['x_t', 'hidden_t_prev', 'cell_t_prev', 'forget_bias', 'param_attr', 'bias_attr', 'name'], varargs=None, keywords=None, defaults=(0.0, None, None, None))
 paddle.fluid.layers.reduce_sum ArgSpec(args=['input', 'dim', 'keep_dim', 'name'], varargs=None, keywords=None, defaults=(None, False, None))
 paddle.fluid.layers.reduce_mean ArgSpec(args=['input', 'dim', 'keep_dim', 'name'], varargs=None, keywords=None, defaults=(None, False, None))

python/paddle/fluid/layers/nn.py

@@ -2793,7 +2793,7 @@ def sequence_expand_as(x, y, name=None):
 
 
 @templatedoc()
-def sequence_pad(x, pad_value, maxlen=None):
+def sequence_pad(x, pad_value, maxlen=None, name=None):
     """
     ${comment}
 
@@ -2807,7 +2807,9 @@ def sequence_pad(x, pad_value, maxlen=None):
             None or any positive int. When it is None, all sequences will be
             padded up to the length of the longest one among them; when it a
             certain positive value, it must be greater than the length of the
-            longest original sequence."
+            longest original sequence.
+        name(str|None): A name for this layer(optional). If set None, the layer
+            will be named automatically.
 
     Returns:
         Variable: The padded sequence batch and the original lengths before
@@ -2844,7 +2846,7 @@ def sequence_pad(x, pad_value, maxlen=None):
     return out, length
 
 
-def sequence_unpad(x, length):
+def sequence_unpad(x, length, name=None):
     """
     Sequence Unpad Layer
 
@@ -2876,6 +2878,8 @@ def sequence_unpad(x, length):
             equal length.
         length(Variable): The Variable that specifies the actual ength of
             sequences after unpadding.
+        name(str|None): A name for this layer(optional). If set None, the layer
+            will be named automatically.
 
     Returns:
         Variable: The Variable contains the unpadded sequences.