code: def remove_user(self, username):
          
  
          sql = '''DELETE FROM user WHERE username = ?'''
          try:
              self._db_curs.execute(sql, (username, ))
              self._db_conn.commit()
          except (sqlite3.OperationalError, sqlite3.IntegrityError) as error:
              raise AuthError(error)
          return self._db_curs.rowcount
docs: Remove user from the SQLite database.
  
              * `username` [string]
                  Username of user to remove.