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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_host_port_names(self, host_name):

 """ return a list of the port names of XIV host """

        port_names = list()
        host = self.get_hosts_by_name(host_name)
        fc_ports = host.fc_ports
        iscsi_ports = host.iscsi_ports
        port_names.extend(fc_ports.split(',') if fc_ports != '' else [])
        port_names.extend(iscsi_ports.split(',') if iscsi_ports != '' else [])
        return port_names