code: def test_variables():
      # clear the backend stack
      ivy.unset_backend()
  
      ivy.set_backend("tensorflow", dynamic=True)
  
      a = tf.Variable(0)
      b = tf.Variable(1)
  
      dyn_cont = ivy.Container({"w": a, "b": b})
      stat_cont = ivy.Container({"w": a, "b": b})
      stat_cont.dynamic_backend = False
  
      ivy.set_backend("torch", dynamic=True)
      assert ivy.current_backend().gradients.is_variable(
          dyn_cont["w"].data
      )
  
      ivy.set_backend("paddle", dynamic=True)
      assert ivy.current_backend().gradients.is_variable(
          dyn_cont["w"].data
      )
  
      assert isinstance(stat_cont["w"], tf.Variable)
  
file_path: ivy/ivy_tests/test_ivy/test_misc/test_backend_utils/test_backend_handler.py
imports: from packaging import version
  import pytest
  import importlib
  import types
  import numpy
  import ivy
  from ivy.utils.backend.handler import _backend_dict
  from ivy_tests.test_ivy.helpers.available_frameworks import _available_frameworks
label_desc: Use image node_id 11 for calling a global function with example usage: test_variables() without return types