code: def __init__(self, weights):
      assert len(weights) > 0
      super(WMAEventWindow, self).__init__(len(weights))
      self.__weights = np.asarray(weights)
  
imports: import numpy
  from pyalgotrade import technical
label_desc: Use image node_id 1 to create a new WMAEventWindow object from inherited base classes: technical with example: obj = WMAEventWindow(weights)