code: def getValue(self):
      ret = None
      if self.windowFull():
          ret = self.getValues().std(ddof=self.__ddof)
      return ret
  
file_path: pyalgotrade/pyalgotrade/technical/stats.py
imports: from pyalgotrade import technical
label_desc: Use image node_id 2 for calling the StdDevEventWindow obj's underlying member method code with example usage: obj.getValue() and returns: ret