class_docstr: Image captioning model.
docstr: Single image to resized and normalized image.
docstr_tok: ["Single","image","to","resized","and","normalized","image","."]
code: def prepare(self, img):
      """Single image to resized and normalized image."""
      return self.feat_extractor.prepare(img)
  
imports: import numpy
  import chainer
  from chainer import functions
  from chainer import initializers
  from chainer import links
  from chainer import reporter
  from chainer import Variable
label_desc: Use image node_id 2 for calling the ImageCaptionModel obj's underlying member method code with example usage: obj.prepare(img) and returns: self