Just assign model.state_dict() to a variable, and then call model.load_state_dict() on the variable to load the weights back. See the example below.
from torchvision.models import resnet
states =[]
model = resnet.resnet18()

states.append(model.state_dict())

model.load_state_dict(states[0])

Edit: If you want to store the weight on the GPU then:
model = resnet.resnet18().cuda()
model2 = model
...
model = model2
del model2