code: def load_data(self, path, *args, **kwargs):
          
          self.df = self._load(path,*args, **kwargs)
          self.series = self.df.iloc[:,0]
          print ("Success! file length: " +str(self.df.shape[0]))
docs: see print instance.doc, e.g. cat=LoadFile(kind='excel')
            read how to use cat.load_data, exec: print (cat.doc)