Initialization of VGG layer weights in pytorch

In config file, VGG layer weights are initialized using this way:

from easydict import EasyDict as edict
MODEL = edict()
MODEL.VGG_LAYER_WEIGHTS = dict(conv3_4=1/8, conv4_4=1/4, conv5_4=1/2)

But how to initialize it using a parser? I have tried to do this the following way:

parser.add_argument(’–VGG_LAYER_WEIGHTS’,type=dict, default=conv3_4=1/8, conv4_4=1/4, conv5_4=1/2, help=‘VGG_LAYER_WEIGHTS’)

But got error. Please help me to write it correctly.