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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 load_pa11y_results(stdout, spider, url):
 """ Load output from pa11y, filtering out the ignored messages. The `stdout` parameter is a bytestring, not a unicode string. """

    if not stdout:
        return []

    results = json.loads(stdout.decode('utf8'))

    ignore_rules = ignore_rules_for_url(spider, url)
    for rule in ignore_rules:
        results = [
            result for result in results
            if not ignore_rule_matches_result(rule, result)
        ]
    return results