class_docstr: This is used to create external functions for ccompiler.
  A simple annotator that creates the following program:
         |
    -- begin --
         |
        add
         |
      subtract
         |
      multiply
         |
     -- end --
         |
code: def __init__(self):
      super(CcompilerAnnotator, self).__init__()
      self.in_compiler = 0
  
imports: from tvm import relay
  from tvm.relay.expr_functor import ExprMutator
  from tvm.relay.op.annotation import compiler_begin, compiler_end
label_desc: Use image node_id 1 to create a new CcompilerAnnotator object from inherited base classes: ExprMutator with example: obj = CcompilerAnnotator()