code: def test_issue_1966(self):
      self.assertEqual(
          run(
              """rule cat
    command = cat $rspfile $rspfile > $out
    rspfile = cat.rsp
    rspfile_content = a b c
  
  build a: cat
  """,
              "-j3",
          ),
          """[1/1] cat cat.rsp cat.rsp > a\x1b[K
  """,
      )
  
file_path: ninja/misc/output_test.py
imports: import os
  import platform
  import subprocess
  import sys
  import tempfile
  import unittest
label_desc: Use image node_id 3 for calling the Output obj's underlying member method code with example usage: obj.test_issue_1966() without return types