old_contents: class ApplianceInstance(object):
  
      def __init__(self,traces):
          '''Initialize an appliance trace with a list of traces'''
          self.traces = order_traces(traces)
  
      def add_traces(self,traces):
          '''
          Updates the list of traces to include the traces in the newly supplied
          list of traces.
          '''
          pass # make sure that the trace doesn't overlap with other traces
  
      def get_traces(self):
          '''
          Returns a reference to the list of traces owned by the appliance.
          '''
          return self.traces
  
      def set_traces(self):
          '''
          Sets the list of traces owned by the appliance
          '''
          self.traces = order_traces(traces)
  
      def order_traces(self,traces):
          '''
          Given a set of traces, orders them chronologically and catches
          overlapping traces.
          '''
          return traces
  
new_contents: class ApplianceInstance(object):
  
      def __init__(self,traces):
          '''Initialize an appliance trace with a list of traces'''
          self.traces = order_traces(traces)
  
      def add_traces(self,traces):
          '''
          Updates the list of traces to include the traces in the newly supplied
          list of traces.
          '''
          pass # make sure that the trace doesn't overlap with other traces
  
      def get_traces(self):
          '''
          Returns a reference to the list of traces owned by the appliance.
          '''
          return self.traces
  
      def set_traces(self):
          '''
          Sets the list of traces owned by the appliance
          '''
          self.traces = order_traces(traces)
  
      def order_traces(self,traces):
          '''
          Given a set of traces, orders them chronologically and catches
          overlapping traces.
          '''
          order = np.argsort([s[0] for s in traces.series])
          new_traces = [traces[i] for i in order]
          return new_traces
  
subject: add sorting to instances