code: def wav_to_num_frames_op(wav_audio, frames_per_second):
      """Transforms a wav-encoded audio string into number of frames."""
      res = tf.py_func(
          functools.partial(
              wav_to_num_frames, frames_per_second=frames_per_second
          ),
          [wav_audio],
          tf.int32,
          name="wav_to_num_frames_op",
      )
      res.set_shape(())
      return res
  
imports: import collections
  import functools
  import io
  import re
  import wave
  import zlib
  import librosa
  from magenta.models.onsets_frames_transcription import audio_transform
  from magenta.models.onsets_frames_transcription import constants
  from magenta.models.onsets_frames_transcription import drum_mappings
  from magenta.models.onsets_frames_transcription import melspec_input
  from note_seq import audio_io
  from note_seq import sequences_lib
  from note_seq.protobuf import music_pb2
  import numpy
  import tensorflow.compat.v1
label_desc: Use image node_id 12 for calling a global function with example usage: wav_to_num_frames_op(wav_audio, frames_per_second) and returns: res