I have extended the `SaveModelCallback` so that I can copy my saved models from colab onto gdrive automatically.

SaveAndPersistModel.py

class SaveAndPersistModel(SaveModelCallback):
  def __init__(self , monitor='valid_loss', comp=None, min_delta=0., fname='model', every_epoch=False, add_save=None, with_opt=False, 
               persistence_path:str='./drive/My\ Drive/'):    
    super().__init__(monitor, comp, min_delta, fname, every_epoch, add_save, with_opt)
    self.persistence_path = persistence_path

  def after_epoch(self):  
    super().after_epoch()
    #print(str(self.path/f"{self.fname}.tar.gz"))
    #print(str(self.path/self.model_dir/f"{self.fname}.pth"))
    #print(self.persistence_path)
    subprocess.call(["tar", "-czvf", str(self.path/f"{self.fname}.tar.gz"),
                     str(self.path/self.model_dir/f"{self.fname}.pth")])
    subprocess.call(["cp", self.path/f"{self.fname}.tar.gz", self.persistence_path])

Caveat: My gdrive will be mount at ./drive/My\ Drive/language_model. I had not managed to work with the path, containing a blank. Therefore I have created a symbolic link which worked fine!

subprocess.call(["ln", "-s", "./drive/My\ Drive/language_model", "model_upload"])