Upgrading StyleGAN model using persistence

[VedantDere0104]

with open('old_pickle.pkl', 'rb') as f:
old_net = pickle.load(f)
new_net = MyNetwork(*old_obj.init_args, **old_obj.init_kwargs)
misc.copy_params_and_buffers(old_net, new_net, require_all=True)

while doing this I'm getting error RuntimeError: a leaf Variable that requires grad is being used in an in-place operation.
According to me there is some in-place operation in the old_net.
How to modify old_net code to change the in-place operation?