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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 dmlc_opts(opts):
 """convert from mxnet's opts to dmlc's opts """

    args = ['--num-workers', str(opts.num_workers),
            '--num-servers', str(opts.num_servers),
            '--cluster', opts.launcher,
            '--host-file', opts.hostfile,
            '--sync-dst-dir', opts.sync_dst_dir]

    # convert to dictionary
    dopts = vars(opts)
    for key in ['env_server', 'env_worker', 'env']:
        for v in dopts[key]:
            args.append('--' + key.replace("_","-"))
            args.append(v)
    args += opts.command
    try:
        from dmlc_tracker import opts
    except ImportError:
        print("Can't load dmlc_tracker package.  Perhaps you need to run")
        print("    git submodule update --init --recursive")
        raise
    dmlc_opts = opts.get_opts(args)
    return dmlc_opts