code: def test_float64_fallback():
      dtype = "float64"
      net = nn.Dense(units=3, dtype=dtype)
      in_data = mx.np.random.normal(size=[3, 3, 3, 3], dtype=dtype)
      net.initialize()
      out = net(in_data)
      out.wait_to_read()
      assert in_data.dtype == out.dtype
  
imports: import mxnet
  import pytest
  from subgraph_common import check_fusion, check_neg_fusion, check_neg_fusion_quantized, check_quantize
  from subgraph_common import CustomNormalInit, DATA_SHAPE, TailNegBlock
  from mxnet.contrib import quantization
  from mxnet.gluon import nn
  from mxnet.test_utils import assert_almost_equal_with_err
label_desc: Use image node_id 1 for calling a global function with example usage: test_float64_fallback() without return types