code: def get_terms(self):
          ''' GROUP BY is a shortcut to only getting the first in every list of group '''
          if not self.terms.empty:
              return self.terms
          if self.from_backup:
              self.terms = open_pickle(TERMS_BACKUP_PATH)
              return self.terms
          engine = create_engine(self.db_url)
          data = 
          self.terms = pd.read_sql(data, engine)
          create_pickle(self.terms, TERMS_BACKUP_PATH)
          return self.terms
docs: GROUP BY is a shortcut to only getting the first in every list of group