class_docstr: A NumPy ndarray-like object abstracted as shape and dtype.
  
  Main use is for representing input and output signatures.
code: def as_tuple(self):
      return self.shape, self.dtype
  
file_path: trax/trax/shapes.py
imports: import numpy
  import tensorflow
label_desc: Use image node_id 6 for calling the ShapeDtype obj's underlying member method code with example usage: obj.as_tuple() and returns: self,  self