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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 is_fqdn(hostname):
 """ Verify if hostname conforms to be a FQDN. :param hostname: text string with the name of the host :return: bool, True if hostname is correct FQDN, False otherwise """


    compliant = re.compile(r"(?!-)[A-Z\d\-\_]{1,63}(?<!-)$", re.IGNORECASE)
    return "." in hostname and len(hostname) < 0xff and all(compliant.match(x) for x in hostname.rstrip(".").split("."))