class_docstr: A Base class that every transform method should derived from.
class_docstr_tok: ["A","Base","class","that","every","transform","method","should","derived","from","."]
docstr: Override this method to inform it need vocab to start.
docstr_tok: ["Override","this","method","to","inform","it","need","vocab","to","start","."]
code: def require_vocab(cls):
      """Override this method to inform it need vocab to start."""
      return False
  
imports: import torch
  from onmt.utils.logging import logger
  from onmt.utils.misc import check_path
label_desc: Use image node_id 3 for calling the Transform obj's underlying member method code with example usage: obj.require_vocab(cls) and returns: False