code: def scale_f0_hz(f0_hz):
      """Scales [0, Nyquist] Hz to [0, 1.0] MIDI-scaled."""
      return ddsp.core.hz_to_midi(f0_hz) / F0_RANGE
  
imports: import ddsp
  from ddsp.training import nn
  import gin
  import tensorflow
label_desc: Use image node_id 4 for calling a global function with example usage: scale_f0_hz(f0_hz) and returns: unknown