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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 oldest_peer(peers):
 """Determines who the oldest peer is by comparing unit numbers."""

    local_unit_no = int(os.getenv('JUJU_UNIT_NAME').split('/')[1])
    for peer in peers:
        remote_unit_no = int(peer.split('/')[1])
        if remote_unit_no < local_unit_no:
            return False
    return True