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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 cmd_whois_domain(domain):
 """Simple whois client to check domain names. Example: \b $ habu.whois.domain portantier.com { "domain_name": "portantier.com", "registrar": "Amazon Registrar, Inc.", "whois_server": "whois.registrar.amazon.com", """


    warnings.filterwarnings("ignore")

    data = whois.whois(domain)
    data = remove_duplicates(data)

    print(json.dumps(data, indent=4, default=str))