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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_id(owner, date, content):
 """ Generate an unique Atom id for the given content """

    h = hashlib.sha256()
    # Hash still contains the original project url, keep as is
    h.update("github.com/spacetelescope/asv".encode('utf-8'))
    for x in content:
        if x is None:
            h.update(",".encode('utf-8'))
        else:
            h.update(x.encode('utf-8'))
        h.update(",".encode('utf-8'))

    if date is None:
        date = datetime.datetime(1970, 1, 1)
    return "tag:{0},{1}:/{2}".format(owner, date.strftime('%Y-%m-%d'), h.hexdigest())