class_docstr: Interface for a key in a dask graph.
  
  Subclasses must have .key attribute that refers to a key in a dask graph.
  
  Sometimes we want to associate metadata to keys in a dask graph.  For
  example we might know that that key lives on a particular machine or can
  only be accessed in a certain way.  Schedulers may have particular needs
  that can only be addressed by additional metadata.
class_docstr_tok: ["Interface","for","a","key","in","a","dask","graph",".","Subclasses","must","have",".key","attribute","that","refers","to","a","key","in","a","dask","graph",".","Sometimes","we","want","to","associate","metadata","to","keys","in","a","dask","graph",".","For","example","we","might","know","that","that","key","lives","on","a","particular","machine","or","can","only","be","accessed","in","a","certain","way",".","Schedulers","may","have","particular","needs","that","can","only","be","addressed","by","additional","metadata","."]
code: def __repr__(self):
      return f"{type(self).__name__}('{self.key}')"
  
imports: from __future__ import annotations
  import asyncio
  import logging
  import random
  from collections import defaultdict
  from collections.abc import Callable, Collection, Coroutine, Mapping
  from functools import partial
  from itertools import cycle
  from typing import Any, TypeVar
  from tlz import concat, drop, groupby, merge
  import dask.config
  from dask.optimization import SubgraphCallable
  from dask.typing import Key
  from dask.utils import is_namedtuple_instance, parse_timedelta
  from distributed.core import ConnectionPool, rpc
  from distributed.utils import All
label_desc: Use image node_id 2 for calling the WrappedKey obj's underlying member method code with example usage: obj.__repr__() and returns: type, str, self, str