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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 to_hosts(hosts, default_protocol='telnet', default_domain=''):
 """ Given a string or a Host object, or a list of strings or Host objects, this function returns a list of Host objects. :type hosts: string|Host|list(string)|list(Host) :param hosts: One or more hosts or hostnames. :type default_protocol: str :param default_protocol: Passed to the Host constructor. :type default_domain: str :param default_domain: Appended to each hostname that has no domain. :rtype: list[Host] :return: A list of Host objects. """

    return [to_host(h, default_protocol, default_domain)
            for h in to_list(hosts)]