code: def check_audio(audio_file):
      assert audio_file.endswith(
          ".wav"
      ), "Input file must be a wave file `*.wav`."
      sig, sample_rate = load(audio_file)
      if sample_rate != 16000:
          sig, _ = load(audio_file, 16000)
          audio_file_16k = (
              audio_file[: audio_file.rindex(".")] + "_16k.wav"
          )
          logger.info(
              "Resampling to 16000 sample rate to new audio file: {}".format(
                  audio_file_16k
              )
          )
          save_wav(sig, 16000, audio_file_16k)
          return audio_file_16k
      else:
          return audio_file
  
file_path: PaddleHub/modules/audio/asr/u2_conformer_wenetspeech/module.py
imports: import os
  import paddle
  from paddleaudio import load, save_wav
  from paddlespeech.cli import ASRExecutor
  from paddlehub.module.module import moduleinfo, serving
  from paddlehub.utils.log import logger
label_desc: Use image node_id 2 for calling the U2Conformer obj's underlying member method code with example usage: obj.check_audio(audio_file) and returns: audio_file_16k, audio_file