docstr: A proxy-call to the dataframe's `.expanding()`.
code: def expanding(self, min_periods):
      """
      A proxy-call to the dataframe's `.expanding()`.
      """
      return self.dataframe.expanding(min_periods=min_periods)
  
imports: from abc import ABC
label_desc: Use image node_id 41 for calling the DataframeAbstract obj's underlying member method code with example usage: obj.expanding(min_periods) and returns: self