code: def test_clear_cached_mem_on_dev(backend_fw):
      with BackendHandler.update_backend(backend_fw) as ivy_backend:
          devices = _get_possible_devices()
          for device in devices:
              # Testing on only GPU since clearing cache mem is relevant
              # for only CUDA devices
              if "gpu" in device:
                  arr = ivy_backend.random_normal(  # noqa: F841
                      shape=(10000, 1000),
                      dtype="float32",
                      device=device,
                  )
                  del arr
                  before = get_gpu_mem_usage(device)
                  ivy_backend.clear_cached_mem_on_dev(device)
                  after = get_gpu_mem_usage(device)
                  assert before > after
  
imports: import io
  import multiprocessing
  import os
  import re
  import shutil
  import sys
  import warnings
  import numpy
  import psutil
  import subprocess
  from hypothesis import strategies, assume
  import ivy
  import ivy_tests.test_ivy.helpers
  import ivy_tests.test_ivy.helpers.globals
  from ivy_tests.test_ivy.helpers import handle_test, BackendHandler
label_desc: Use image node_id 11 for calling a global function with example usage: test_clear_cached_mem_on_dev(backend_fw) without return types