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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def userdata_to_db(session, method='update', autocommit=False):
 """ Add catchments from a user folder to the database. The user folder is specified in the ``config.ini`` file like this:: [import] folder = path/to/import/folder If this configuration key does not exist this will be silently ignored. :param session: database session to use, typically `floodestimation.db.Session()` :type session: :class:`sqlalchemy.orm.session.Session` :param method: - ``create``: only new catchments will be loaded, it must not already exist in the database. - ``update``: any existing catchment in the database will be updated. Otherwise it will be created. :type method: str :param autocommit: Whether to commit the database session immediately. Default: ``False``. :type autocommit: bool """


    try:
        folder = config['import']['folder']
    except KeyError:
        return
    if folder:
        folder_to_db(folder, session, method=method, autocommit=autocommit)