code: def multidevice_test(fxn):
      exclude_devices = getenv("EXCLUDE_DEVICES", "").split(",")
  
      def ret(self):
          for device in Device._devices:
              if device in ["DISK", "FAKE"]:
                  continue
              if not CI:
                  print(device)
              if device in exclude_devices:
                  if not CI:
                      print(f"WARNING: {device} test is excluded")
                  continue
              with self.subTest(device=device):
                  try:
                      Device[device]
                  except Exception:
                      if not CI:
                          print(f"WARNING: {device} test isn't running")
                      continue
                  fxn(self, device)
  
      return ret
  
file_path: tinygrad/test/external/external_test_example.py
imports: import unittest
  from tinygrad import Device
  from tinygrad.tensor import Tensor
  from tinygrad.helpers import getenv, CI
label_desc: Use image node_id 1 for calling a global function with example usage: multidevice_test(fxn) and returns: ret