old_contents: #!/usr/bin/env python
  
  class SimError(Exception):
  	pass
  
  class SimIRSBError(SimError):
  	pass
  
  class SimModeError(SimError):
  	pass
  
  class SimProcedureError(Exception):
  	pass
  
  class SimMergeError(Exception):
  	pass
  
  class SimValueError(Exception):
  	pass
  
  class SimUnsatError(SimValueError):
  	pass
  
  class SimMemoryError(SimError):
  	pass
  
  
new_contents: #!/usr/bin/env python
  
  class SimError(Exception):
  	pass
  
  class SimIRSBError(SimError):
  	pass
  
  class SimModeError(SimError):
  	pass
  
  class SimProcedureError(SimError):
  	pass
  
  class SimMergeError(SimError):
  	pass
  
  class SimValueError(SimError):
  	pass
  
  class SimUnsatError(SimValueError):
  	pass
  
  class SimMemoryError(SimError):
  	pass
  
  
subject: make things derive from SimError