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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 _check_if_must_download(request_list, redownload):
 """ Updates request.will_download attribute of each request in request_list. **Note:** the function mutates the elements of the list! :param request_list: a list of ``DownloadRequest`` instances :type: list[DownloadRequest] :param redownload: tells whether to download the data again or not :type: bool """

    for request in request_list:
        request.will_download = (request.save_response or request.return_data) \
                                and (not request.is_downloaded() or redownload)