class_docstr: Coloring a chunk graph according to an algorithm
  described in https://github.com/mars-project/mars/issues/2435
class_docstr_tok: ["Coloring","a","chunk","graph","according","to","an","algorithm","described","in","https",":","\/\/github.com\/mars-project\/mars\/issues\/2435"]
code: def next_color(self) -> int:
      return next(self._coloring_iter)
  
file_path: mars/mars/services/task/analyzer/fusion.py
imports: import itertools
  from collections import defaultdict
  from typing import Dict, List
  from ....config import options
  from ....core import ChunkGraph
  from ....core.operand import VirtualOperand
  from ....typing import BandType, ChunkType, OperandType
label_desc: Use image node_id 2 for calling the Coloring obj's underlying member method code with example usage: obj.next_color() and returns: next