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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 serialize_seeds(seeds, block):
 """ Serialize the seeds in peer instruction XBlock to xml Args: seeds (lxml.etree.Element):
 The <seeds> XML element. block (PeerInstructionXBlock):
 The XBlock with configuration to serialize. Returns: None """

    for seed_dict in block.seeds:
        seed = etree.SubElement(seeds, 'seed')
        # options in xml starts with 1
        seed.set('option', unicode(seed_dict.get('answer', 0) + 1))
        seed.text = seed_dict.get('rationale', '')