chunk_content: Prefix tuning for conditional generation
  	
  
  
  
  
  
  
  
  
  
  
  
  Prefix tuning is an additive method where only a sequence of continuous task-specific vectors is attached to the beginning of the input, or prefix. Only the prefix parameters are optimized and added to the hidden states in every layer of the model. The tokens of the input sequence can still attend to the prefix as virtual tokens. As a result, prefix tuning stores 1000x fewer parameters than 