code: def revision_heads_map():
      rh_map = {}
      pattern = r'revision = "[a-fA-F0-9]+"'
      airflow_version_pattern = r'airflow_version = "\d+\.\d+\.\d+"'
      filenames = os.listdir(MIGRATION_PATH)
  
      def sorting_key(filen):
          prefix = filen.split("_")[0]
          return int(prefix) if prefix.isdigit() else 0
  
      sorted_filenames = sorted(filenames, key=sorting_key)
  
      for filename in sorted_filenames:
          if not filename.endswith(".py"):
              continue
          with open(os.path.join(MIGRATION_PATH, filename)) as file:
              content = file.read()
              revision_match = re2.search(pattern, content)
              airflow_version_match = re2.search(
                  airflow_version_pattern, content
              )
              if revision_match and airflow_version_match:
                  revision = revision_match.group(0).split('"')[1]
                  version = airflow_version_match.group(0).split('"')[1]
                  if parse_version(version) >= parse_version("2.0.0"):
                      rh_map[version] = revision
      return rh_map
  
imports: from __future__ import annotations
  import os
  import sys
  from pathlib import Path
  import re2
  from packaging.version import parse
label_desc: Use image node_id 1 for calling a global function with example usage: revision_heads_map() and returns: rh_map, unknown