docstr: A proxy-call to the dataframe's `.duplicated()`.
code: def duplicated(self):
      """
      A proxy-call to the dataframe's `.duplicated()`.
      """
      return self.dataframe.duplicated()
  
imports: from abc import ABC
label_desc: Use image node_id 15 for calling the DataframeAbstract obj's underlying member method code with example usage: obj.duplicated() and returns: self