code: def load(self):
          
          # read file, keep all values as strings
          df = pd.read_csv(self.input_file,
                           sep=',',
                           quotechar='"',
                           encoding='utf-8',
                           dtype=object)
  
          # wer are only interested in the NUTS code and description, rename them also
          df = df[['NUTS-Code', 'Description']]
          df.columns = ['key', 'name']
  
          # we only want NUTS2 regions (4-digit codes)
          df = df[df['key'].str.len() == 4]
  
          # drop 'Extra Regio' codes ending in 'ZZ'
          df = df[df['key'].str[2:] != 'ZZ']
  
          return df
docs: Load data, from default location
  
          Returns:
              pandas.DataFrame: columns 'key' (NUTS2 code), 'name'