code: def test_variables_list(self):
      self.n.build("out", "cc", "in", variables=[("name", "value")])
      self.assertEqual(
          """\
  build out: cc in
    name = value
  """,
          self.out.getvalue(),
      )
  
imports: import unittest
  import ninja_syntax
label_desc: Use image node_id 3 for calling the TestBuild obj's underlying member method code with example usage: obj.test_variables_list() without return types