code: def test_dev(*, dtype_and_x, test_flags, backend_fw):
      dtype, x = dtype_and_x
      dtype = dtype[0]
      x = x[0]
  
      with BackendHandler.update_backend(backend_fw) as ivy_backend:
          for device in _get_possible_devices():
              x = ivy_backend.array(x, device=device)
              if test_flags.as_variable and ivy_backend.is_float_dtype(
                  dtype
              ):
                  x = ivy_backend.functional.ivy.gradients._variable(x)
  
              ret = ivy_backend.dev(x)
              # type test
              assert isinstance(ret, str)
              # value test
              assert ret == device
              # array instance test
              assert x.dev() == device
              # container instance test
              container_x = ivy_backend.Container({"a": x})
              assert container_x.dev() == device
              # container static test
              assert (
                  ivy_backend.Container.static_dev(container_x)
                  == device
              )
  
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 13 for calling a global function with example usage: test_dev() without return types