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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_api_sig(args):
 """Flickr API need a hash string which made using post arguments :param args: Arguments of the flickr request :type args: list of sets :return: api_sig, ex: ('api_sig', 'abcdefg') :rtype: tuple """

    tmp_sig = api_secret
    for i in args:
        tmp_sig = tmp_sig + i[0] + i[1]
    api_sig = hashlib.md5(tmp_sig.encode('utf-8')).hexdigest()
    return 'api_sig', api_sig