class_docstr: Test Pipeline
class_docstr_tok: ["Test","Pipeline"]
code: def test_concat_multi_pipe(self):
      pipe0 = Pipeline.input("a", "b", "c")
      pipe1 = pipe0.map("a", "d", ops.add_operator(10))
      pipe2 = pipe0.map(("b", "c"), "e", ops.sub_operator())
      pipe3 = pipe0.map(("b", "c"), "f", lambda x, y: x * y)
      pipe4 = pipe3.concat(pipe1, pipe2).output("d", "e", "f")
  
      d, e, f = pipe4(1, 2, 3).get()
      self.assertEqual(d, 11)
      self.assertEqual(e, -1)
      self.assertEqual(f, 6)
  
imports: import unittest
  from towhee.operator.nop import NOPNodeOperator
  from towhee.operator import PyOperator
  from towhee.runtime.pipeline import Pipeline
  from towhee.runtime.data_queue import Empty
  from towhee.runtime import ops, register
  from towhee.runtime.runtime_pipeline import RuntimePipeline
label_desc: Use image node_id 13 for calling the TestPipeline obj's underlying member method code with example usage: obj.test_concat_multi_pipe() without return types