class_docstr: GraphItem is a TensorFlow Graph wrapper.
  
  It represents the states in-between consecutive AutoDist.kernel graph transformations.
  tf.Graph is the primary property of GraphItem, whereas MetaGraph is exported/generated on demand.
  
  A GraphItem can be constructed with either a `tf.Graph` or a `GraphDef`.
docstr: Get the binding op for a given colocation group.
  
  Args:
      colocation_group (bytes): The colocation group
  
  Returns:
      Op
docstr_tok: ["Get","the","binding","op","for","a","given","colocation","group",".","Args",":","colocation_group","(","bytes",")",":","The","colocation","group","Returns",":","Op"]
code: def get_colocation_op(self, colocation_group):
      """
      Get the binding op for a given colocation group.
  
      Args:
          colocation_group (bytes): The colocation group
  
      Returns:
          Op
      """
      assert colocation_group.startswith(COLOCATION_PREFIX)
      binding_op_name = colocation_group[
          len(COLOCATION_PREFIX) :
      ].decode("utf-8")
      return self.graph.get_operation_by_name(binding_op_name)
  
imports: import contextlib
  import copy
  import functools
  from collections import defaultdict
  from typing import Union, Callable
  from google.protobuf.any_pb2 import Any
  from tensorflow.core.framework.graph_pb2 import GraphDef
  from tensorflow.core.framework.variable_pb2 import VariableDef
  from tensorflow.core.protobuf.saver_pb2 import SaverDef
  from tensorflow.python.framework import ops
  from tensorflow.python.framework.importer import import_graph_def
  from tensorflow.python.ops.resource_variable_ops import _from_proto_fn
  from tensorflow.python.ops.variables import Variable
  from autodist.const import COLOCATION_PREFIX
  from autodist.kernel.common import op_info
  from autodist.kernel.common.utils import parse_name_scope, get_op_name
  from autodist.proto import graphitem_pb2
  from autodist.utils import logging
label_desc: Use image node_id 20 for calling the GraphItem obj's underlying member method code with example usage: obj.get_colocation_op(colocation_group) and returns: self