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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 export(results_dir, filename, do_not_try_parsing, parameters):
 """ Export results to file. An extension in filename is required to deduce the file type. If no extension is specified, a directory tree export will be used. Note that this command automatically tries to parse the simulation output. Supported extensions: .mat (Matlab file), .npy (Numpy file), no extension (Directory tree) """


    # Get the extension
    _, extension = os.path.splitext(filename)

    campaign = sem.CampaignManager.load(results_dir)

    [params, defaults] = zip(*get_params_and_defaults(campaign.db.get_params(),
                                                      campaign.db))

    if do_not_try_parsing:
        parsing_function = None
    else:
        parsing_function = sem.utils.automatic_parser

    if not parameters:
        # Convert to string
        string_defaults = list()
        for idx, d in enumerate(defaults):
            string_defaults.append(str(d))
        parameter_query = query_parameters(params, string_defaults)
    else:
        # Import specified parameter file
        parameter_query = import_parameters_from_file(parameters)

    if extension == ".mat":
        campaign.save_to_mat_file(parameter_query, parsing_function, filename,
                                  runs=click.prompt("Runs", type=int))
    elif extension == ".npy":
        campaign.save_to_npy_file(parameter_query, parsing_function, filename,
                                  runs=click.prompt("Runs", type=int))
    elif extension == "":
        campaign.save_to_folders(parameter_query, filename,
                                 runs=click.prompt("Runs", type=int))
    else:  # Unrecognized format
        raise ValueError("Format not recognized")