code: def global_norm(t_list, name=None):
      l2_norms = [
          ivy.sqrt(ivy.sum(ivy.square(t))) ** 2
          for t in t_list
          if t is not None
      ]
      return ivy.sqrt(
          ivy.sum(ivy.asarray(l2_norms, dtype=ivy.dtype(l2_norms[0])))
      )
  
imports: import ivy
  from ivy.functional.frontends.tensorflow import check_tensorflow_casting
  from ivy.func_wrapper import with_unsupported_dtypes, with_supported_dtypes
  from ivy.functional.frontends.tensorflow.func_wrapper import to_ivy_arrays_and_back, handle_tf_dtype
  import ivy.functional.frontends.tensorflow
label_desc: Use image node_id 15 for calling a global function with example usage: global_norm(t_list, name) and returns: ivy