class_docstr: (Untyped) input containing fundamental properties of all inputs to an
  Operation:
class_docstr_tok: ["(","Untyped",")","input","containing","fundamental","properties","of","all","inputs","to","an","Operation",":"]
docstr: Override this function if datatype can be known without `_default` or
  `_val`.
docstr_tok: ["Override","this","function","if","datatype","can","be","known","without","`","_default","`","or","`","_val","`","."]
code: def _get_predefined_datatype(self):
      """
      Override this function if datatype can be known without `_default` or
      `_val`.
      """
      return None
  
imports: from collections import OrderedDict
  from coremltools.converters.mil.mil import types
  from coremltools.converters.mil.mil.var import InternalVar
label_desc: Use image node_id 4 for calling the _InputType obj's underlying member method code with example usage: obj._get_predefined_datatype() and returns: None