class_docstr: Defines a general datatype.
  
  A :class:`RawField` object does not assume any property of the datatype and
  it holds parameters relating to how a datatype should be processed.
  
  Args:
      name (str):
          The name of the field.
      fn (function):
          The function used for preprocessing the examples. Default: ``None``.
class_docstr_tok: ["Defines","a","general","datatype",".","A",":","class",":","`","RawField","`","object","does","not","assume","any","property","of","the","datatype","and","it","holds","parameters","relating","to","how","a","datatype","should","be","processed",".","Args",":","name","(","str",")",":","The","name","of","the","field",".","fn","(","function",")",":","The","function","used","for","preprocessing","the","examples",".","Default",":","``","None","``","."]
code: def __init__(self, name, fn=None):
      self.name = name
      self.fn = fn
  
imports: from collections import Counter
  import torch
  from underthesea.utils.sp_fn import pad
  from underthesea.utils.sp_vocab import Vocab
label_desc: Use image node_id 1 to create a new RawField object from inherited base classes: object with example: obj = RawField(name, fn)