'StdImage' object has no attribute 'compression'

[nm17]

Expected Behavior

mkimg should extract the image

Actual Behavior

$ mkimg extract <image path>

'StdImage' object has no attribute 'compression'

Steps to Reproduce the Problem

1. Install uboot
2. Unpack the image using mkimg extract

Specifications

• Environment:
  Python 3.6.8

uboot==0.1.1
  - click [required: ==7.0, installed: 7.0]
  - easy-enum [required: ==0.2.0, installed: 0.2.0]
  - fdt [required: ==0.1.2, installed: 0.1.2]
    - click [required: >=5.0, installed: 7.0]

• System: Ubuntu 18.04.2 LTS