code: def set_active_trends(self, trends):
      self.mActiveTrends = {}
      for trend in self.mKnownTrends:
          if trend in trends:
              self.mActiveTrends[trend] = True
          else:
              self.mActiveTrends[trend] = False
      if True not in self.mActiveTrends.values():
          # default
          self.mActiveTrends["ConstantTrend"] = True
  
imports: import pandas
  import numpy
label_desc: Use image node_id 3 for calling the cModelControl obj's underlying member method code with example usage: obj.set_active_trends(trends) without return types