Add a new backbone

Code for this section：

core/model/backbone/*
config/backbones/*

If you want to add a new backbone into LibFewShot, you should put all files about this new backbone in the directory of core/model/backbone/. For example, to add a ResNet to LibFewShot, you need provide a resnet.py in the directory of core/model/backbone/, and provide a class or function that can return a ResNet model like following:

...

class ResNet(nn.Module):
	def __init(self,...):
...

def ResNet18():
	model = ResNet(BasicBlock, [2,2,2,2], **kwargs)
	return model

After that, to make sure trainer.py could call ResNet18, you need add a line in core/model/backbone/__init__.py as follows:

...

from resnet import ResNet18

At this point, the addition of a new backbone is finished.

The new backbone shares the same way to use as other backbones. For example, to change DN4 backbone to the new backbone, you just modify backbone’s value in config/dn4.yaml as follows:

# arch info
backbone:
  name: resnet18
  kwargs:
    avg_pool: False
    is_flatten: False