code: def test_eager_to_compute_dependent_to_free_parent():
      r"""https://github.com/dask/dask/pull/7929
  
      This graph begins with many motifs like the following:
  
      |      |
      c1    c2
        \ /
         b
         |
         a
  
      We want to compute c2 and c3 pretty close together, because if we choose to
      compute c1, then we should also compute c2 so we can release b.  Being
      greedy here allows us to release memory sooner and be more globally optimal.
      """
      dsk = {
          "a00": (f, "a06", "a08"),
          "a01": (f, "a28", "a26"),
          "a02": (f, "a24", "a21"),
          "a03": (f, "a22", "a25"),
          "a04": (f, "a29", "a20"),
          "a05": (f, "a23", "a27"),
          "a06": (f, "a04", "a02"),
          "a07": (f, "a00", "a01"),
          "a08": (f, "a05", "a03"),
          "a09": (f, "a43"),
          "a10": (f, "a36"),
          "a11": (f, "a33"),
          "a12": (f, "a47"),
          "a13": (f, "a44"),
          "a14": (f, "a42"),
          "a15": (f, "a37"),
          "a16": (f, "a48"),
          "a17": (f, "a49"),
          "a18": (f, "a35"),
          "a19": (f, "a46"),
          "a20": (f, "a55"),
          "a21": (f, "a53"),
          "a22": (f, "a60"),
          "a23": (f, "a54"),
          "a24": (f, "a59"),
          "a25": (f, "a56"),
          "a26": (f, "a61"),
          "a27": (f, "a52"),
          "a28": (f, "a57"),
          "a29": (f, "a58"),
          "a30": (f, "a19"),
          "a31": (f, "a07"),
          "a32": (f, "a30", "a31"),
          "a33": (f, "a58"),
          "a34": (f, "a11", "a09"),
          "a35": (f, "a60"),
          "a36": (f, "a52"),
          "a37": (f, "a61"),
          "a38": (f, "a14", "a10"),
          "a39": (f, "a38", "a40"),
          "a40": (f, "a18", "a17"),
          "a41": (f, "a34", "a50"),
          "a42": (f, "a54"),
          "a43": (f, "a55"),
          "a44": (f, "a53"),
          "a45": (f, "a16", "a15"),
          "a46": (f, "a51", "a45"),
          "a47": (f, "a59"),
          "a48": (f, "a57"),
          "a49": (f, "a56"),
          "a50": (f, "a12", "a13"),
          "a51": (f, "a41", "a39"),
          "a52": (f, "a62"),
          "a53": (f, "a68"),
          "a54": (f, "a70"),
          "a55": (f, "a67"),
          "a56": (f, "a71"),
          "a57": (f, "a64"),
          "a58": (f, "a65"),
          "a59": (f, "a63"),
          "a60": (f, "a69"),
          "a61": (f, "a66"),
          "a62": (f, f),
          "a63": (f, f),
          "a64": (f, f),
          "a65": (f, f),
          "a66": (f, f),
          "a67": (f, f),
          "a68": (f, f),
          "a69": (f, f),
          "a70": (f, f),
          "a71": (f, f),
      }
      o = order(dsk)
      assert_topological_sort(dsk, o)
  
      _, pressure = diagnostics(dsk, o=o)
      assert max(pressure) <= 8
      # Visualizing the graph shows that there are two deep, thick branches and
      # two shallow ones. We prefer to run the deep ones first and reduce them as
      # far as possible before starting another computation branch.
      # We don't care about the ordering so deep_roots1 and deep_roots2 are
      # ambiguous. At time of writing, deep_roots1 was executed first.
      shallow_roots = ["a64", "a66"]
      deep_roots1 = ["a68", "a63", "a65", "a67"]
      # These are the final reducers of the first, thick branch
      reducers_1 = ["a06", "a41"]
      deep_roots2 = ["a69", "a70", "a71", "a62"]
      reducers_2 = ["a39", "a00"]
      for deep_roots in [deep_roots1, deep_roots2]:
          assert max(o[r] for r in deep_roots) < min(
              o[r] for r in shallow_roots
          )
      # These two are the reduction nodes furthest along before additional roots
      # have to be loaded
      for reducer in [reducers_1, reducers_2]:
          for red in reducer:
              assert o[red] < min(o[r] for r in shallow_roots)
  
imports: from __future__ import annotations
  import inspect
  import pytest
  import dask
  from dask import delayed
  from dask.base import collections_to_dsk, key_split, visualize_dsk
  from dask.core import get_deps
  from dask.order import _connecting_to_roots, diagnostics, ndependencies, order
  from dask.utils_test import add, inc
label_desc: Use image node_id 33 for calling a global function with example usage: test_eager_to_compute_dependent_to_free_parent() without return types