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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 _torque_queue_nodes(queue):
 """Retrieve the nodes available for a queue. Parses out nodes from `acl_hosts` in qstat -Qf and extracts the initial names of nodes used in pbsnodes. """

    qstat_out = subprocess.check_output(["qstat", "-Qf", queue]).decode()
    hosts = []
    in_hosts = False
    for line in qstat_out.split("\n"):
        if line.strip().startswith("acl_hosts = "):
            hosts.extend(line.replace("acl_hosts = ", "").strip().split(","))
            in_hosts = True
        elif in_hosts:
            if line.find(" = ") > 0:
                break
            else:
                hosts.extend(line.strip().split(","))
    return tuple([h.split(".")[0].strip() for h in hosts if h.strip()])