old_contents: from ophyd import PVPositionerPC, EpicsSignal, EpicsSignalRO
  from ophyd import Component as Cpt
  
  # Undulator
  
  class Undulator(PVPositionerPC):
      readback = Cpt(EpicsSignalRO, '-LEnc}Gap')
      setpoint = Cpt(EpicsSignal, '-Mtr:2}Inp:Pos')
      actuate = Cpt(EpicsSignal, '-Mtr:2}Sw:Go')
      actuate_value = 1
      stop_signal = Cpt(EpicsSignal, '-Mtr:2}Pos.STOP')
      stop_value = 1
  
  ivu_gap = Undulator('SR:C11-ID:G1{IVU20:1')
  
  # This class is defined in 10-optics.py
  fe = VirtualMotorCenterAndGap('FE:C11A-OP{Slt:12') # Front End Slits (Primary Slits)
  
new_contents: from ophyd import PVPositionerPC, EpicsSignal, EpicsSignalRO
  from ophyd import Component as Cpt
  
  # Undulator
  
  class Undulator(PVPositionerPC):
      readback = Cpt(EpicsSignalRO, '-LEnc}Gap')
      setpoint = Cpt(EpicsSignal, '-Mtr:2}Inp:Pos')
      actuate = Cpt(EpicsSignal, '-Mtr:2}Sw:Go')
      actuate_value = 1
      stop_signal = Cpt(EpicsSignal, '-Mtr:2}Pos.STOP')
      stop_value = 1
  
  ivu_gap = Undulator('SR:C11-ID:G1{IVU20:1', name='ivu_gap')
  
  # This class is defined in 10-optics.py
  fe = VirtualMotorCenterAndGap('FE:C11A-OP{Slt:12', name='fe') # Front End Slits (Primary Slits)
  
subject: add missing name kwarg