Load the data file, do some basic type conversions

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