code: def getValue(self):
      ret = None
      if self.windowFull():
          accum = (self.getValues() * self.__weights).sum()
          weightSum = self.__weights.sum()
          ret = accum / float(weightSum)
      return ret
  
imports: import numpy
  from pyalgotrade import technical
label_desc: Use image node_id 2 for calling the WMAEventWindow obj's underlying member method code with example usage: obj.getValue() and returns: ret