code: def setUp(self):
      config.set_backend("torch")
  
      asia = get_example_model("asia")
      self.writer = NETWriter(asia)
  
imports: import unittest
  import numpy
  from pgmpy import config
  from pgmpy.readwrite import NETReader, NETWriter
  from pgmpy.utils import compat_fns, get_example_model
label_desc: Use image node_id 1 for calling the TestNETWriterTorch obj's underlying member method code with example usage: obj.setUp() without return types