code: def filter_params(self, value):
          
          if value is None:
              return {}
  
          val_min = value.get('min', None)
          val_max = value.get('max', None)
          params = {}
  
          if val_min == val_max:
              return { self.target: val_min }
  
          key = self.target + "__"
          if val_min is not None:
              params[key+self.lookup_types[0]] = val_min
          if val_max is not None:
              params[key+self.lookup_types[1]] = val_max
  
          return params
docs: return filtering params