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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 get_storage():
 """ Get storage object of current app context, will create a new one if not exists. :return: a storage object :raise: ConfigurationError: storage type in config is not supported """

    storage_ = getattr(g, '_storage', None)
    if storage_ is None:
        storage_type = current_app.config['STORAGE_TYPE']
        if storage_type == 'file':
            storage_ = g._storage = storages.FileStorage()
        else:
            raise ConfigurationError(
                'Storage type "{}" is not supported.'.format(storage_type))
    return storage_