looking for keras development kit

[lfrcoder]

Can you show me the keras development kit used? Because I have the following problem:
Using TensorFlow backend.
Traceback (most recent call last):
   File "train.py", line 17, in
     From models.model_factory import Model_Factory
   File "/home/liufangrui/mcv-m5-master/code/models/model_factory.py", line 19, in
     From models.yolo import build_yolo
   File "/home/liufangrui/mcv-m5-master/code/models/yolo.py", line 10, in
     From layers.yolo_layers import YOLOConvolution2D, Reorg
   File "/home/liufangrui/mcv-m5-master/code/layers/yolo_layers.py", line 7, in
     From keras.utils.np_utils import conv_output_length
ImportError: cannot import name conv_output_length