diff --git a/caffe2fluid/kaffe/custom_layers/detection_out.py b/caffe2fluid/kaffe/custom_layers/detection_out.py
index ff79e2649efd37cc40f2905f6d97b6fb8103676c..54e0f68bc14ccba3d7b925aa93d3a851cf5e0661 100644
--- a/caffe2fluid/kaffe/custom_layers/detection_out.py
+++ b/caffe2fluid/kaffe/custom_layers/detection_out.py
@@ -49,13 +49,13 @@ def detectionoutput_layer(inputs,
     pbv = fluid.layers.reshape(x=pbv, shape=[-1, 4])
     mbox_loc = inputs[0]
     mbox_loc = fluid.layers.reshape(
-        x=mbox_loc, shape=[-1, mbox_conf_flatten.shape[1], 4])
+        x=mbox_loc, shape=[0, mbox_conf_flatten.shape[1], 4])
 
     default = {"nms_threshold": 0.3, "top_k": 10, "eta": 1.0}
     fields = ['eta', 'top_k', 'nms_threshold']
 
     for f in default.keys():
-        if not nms_param.has_key(f):
+        if f not in nms_param:
             nms_param[f] = default[f]
 
     nmsed_outs = fluid.layers.detection_output(
diff --git a/caffe2fluid/kaffe/custom_layers/flatten.py b/caffe2fluid/kaffe/custom_layers/flatten.py
index ebb97718e3294bb473752bc6235917bed0db0650..271cc99f790976ed463dfcfdae5527b052a9cc97 100644
--- a/caffe2fluid/kaffe/custom_layers/flatten.py
+++ b/caffe2fluid/kaffe/custom_layers/flatten.py
@@ -2,7 +2,7 @@
     more info can be found here: http://caffe.berkeleyvision.org/tutorial/layers/flatten.html
 """
 from .register import register
-
+from functools import reduce
 
 def flatten_shape(input_shape, axis=1, end_axis=-1):
     """ calculate the output shape of this layer using input shape
@@ -29,6 +29,8 @@ def flatten_shape(input_shape, axis=1, end_axis=-1):
             % (start_axis, end_axis)
     output_shape = input_shape[0:start_axis]
     flat_sz = reduce(lambda a, b: a * b, input_shape[start_axis:end_axis])
+    if flat_sz < 0:
+        flat_sz = -1
     output_shape += [flat_sz]
     output_shape += input_shape[end_axis:-1]
 
@@ -52,9 +54,8 @@ def flatten_layer(input, name, axis=1, end_axis=-1):
     input_shape = list(input.shape)
 
     if input_shape[0] == -1:
-        input_shape[0] = 1
+        input_shape[0] = 0
         output_shape = flatten_shape(input_shape, axis=axis, end_axis=end_axis)
-        output_shape[0] = -1
     else:
         output_shape = flatten_shape(input_shape, axis=axis, end_axis=end_axis)
 
diff --git a/caffe2fluid/kaffe/custom_layers/reshape.py b/caffe2fluid/kaffe/custom_layers/reshape.py
index b4ec051d7b4f349079f81de874aef9cdf2d18a65..fc2da276683fc70bc83f85199aaf94d794009082 100644
--- a/caffe2fluid/kaffe/custom_layers/reshape.py
+++ b/caffe2fluid/kaffe/custom_layers/reshape.py
@@ -79,11 +79,7 @@ def reshape_layer(input, name, shape, axis=0, num_axes=-1):
         output (variable): output variable for this layer
     """
     fluid = import_fluid()
-
     input_shape = list(input.shape)
-    print(input_shape)
-    print(shape)
-
     if input_shape[0] == -1:
         input_shape[0] = 0
         output_shape = reshape_shape(input_shape, shape, axis, num_axes)