class_docstr: TypeCast data from dataloader at `index` to dtype and move into
  device memory if not already.
code: def transform(self, t):
      self.output[:] = t
      return self.output
  
imports: from __future__ import division
  import numpy
  from neon import NervanaObject
label_desc: Use image node_id 2 for calling the TypeCast obj's underlying member method code with example usage: obj.transform(t) and returns: self