code: def _discover_backends():
      backends = dict()
      root = os.path.dirname(__file__)
      for name in os.listdir(root):
          if not os.path.isdir(os.path.join(root, name)):
              continue
          if name.startswith("__"):
              continue
          compiler = _load_module(
              name, os.path.join(root, name, "compiler.py")
          )
          driver = _load_module(
              name, os.path.join(root, name, "driver.py")
          )
          backends[name] = Backend(
              _find_concrete_subclasses(compiler, BaseBackend),
              _find_concrete_subclasses(driver, DriverBase),
          )
      return backends
  
file_path: triton/python/triton/backends/__init__.py
imports: import os
  import importlib.util
  import inspect
  from dataclasses import dataclass
  from .driver import DriverBase
  from .compiler import BaseBackend
label_desc: Use image node_id 3 for calling a global function with example usage: _discover_backends() and returns: backends