docs: def load(self):
          """Load the data file, do some basic type conversions
          """
  
          df = pd.read_csv(self.input_file,
                           encoding='utf8')
  
          df['wiki_id'] = df['painting'].str.split('/').str[-1]
          df['creator_wiki_id'] = df['creator'].str.split('/').str[-1]
          df['decade'] = (df['inception'].str[:4].astype(float) / 10.).astype(int) * 10
          df['area'] = df['width'] * df['height']
  
          return df