code: def test_group_norm_is_float(self):
      m = nn.GroupNorm(num_groups=4, num_channels=self.c)
      run_layer_test(
          self, [m], ALWAYS_FLOAT, (self.b, self.c, self.h, self.h)
      )
  
imports: import unittest
  import functools
  import itertools
  from apex import amp
  import torch
  from torch import nn
  import torch.nn.functional
  from utils import common_init, HALF, FLOAT, ALWAYS_HALF, ALWAYS_FLOAT, MATCH_INPUT
label_desc: Use image node_id 6 for calling the TestBasicCasts obj's underlying member method code with example usage: obj.test_group_norm_is_float() without return types