class_docstr: Abstract base class for time stretching
  
  This contains the deformation functions and
  annotation query mapping, but does not manage
  state or parameters.
code: def deform_tempo(annotation, state):
      # Deform a tempo annotation
  
      for obs in annotation.pop_data():
          annotation.append(
              time=obs.time,
              duration=obs.duration,
              confidence=obs.confidence,
              value=state["rate"] * obs.value,
          )
  
imports: import pyrubberband
  import numpy
  from ..base import BaseTransformer, _get_rng
label_desc: Use image node_id 4 for calling the AbstractTimeStretch obj's underlying member method code with example usage: obj.deform_tempo(annotation, state) without return types