code: def dense(width, height):
      """Full barriers between each step"""
      d = {("x", 0, i): i for i in range(width)}
      for j in range(1, height):
          d.update(
              {
                  ("x", j, i): (
                      noop,
                      [("x", j - 1, k) for k in range(width)],
                  )
                  for i in range(width)
              }
          )
      return d, [("x", height - 1, i) for i in range(width)]
  
file_path: dask/docs/source/scripts/scheduling.py
imports: from __future__ import annotations
  from random import randint
  from time import time
  import matplotlib.pyplot
  import dask
  from dask import local, multiprocessing, threaded
  import numpy
label_desc: Use image node_id 4 for calling a global function with example usage: dense(width, height) and returns: d,  unknown