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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 estimate(args, **kwargs):
 """ Return a point estimate of the model parameters theta given the data. """


    expected_output_files = kwargs.pop("expected_output_files", None)
    if not expected_output_files:
        expected_output_files = ["estimate.pkl"]
        if args.plotting:
            expected_output_files.extend(
                ["projection-estimate.{}".format(args.plot_format)])
        
    model, data, metadata = _pre_solving(args, expected_output_files)

    try:
        theta, chisq, dof, model_fluxes = model.estimate(data, full_output=True,
            debug=args.debug)

    except:
        logger.exception("Failed to estimate model parameters")
        raise

    logger.info("Estimated model parameters are:")
    _announce_theta(theta)
    logger.info("With a chi-sq value of {0:.1f} (reduced {1:.1f}; DOF {2:.1f})"\
        .format(chisq, chisq/dof, dof))

    metadata["estimated"] = {
        "theta": theta,
        "chi_sq": chisq,
        "dof": dof,
        "r_chi_sq": chisq/dof
    }

    if args.plotting:
        fig = sick.plot.spectrum(data, model_flux=model_fluxes)
        filename = _prefix(args, "projection-estimate.{}".format(
            args.plot_format))
        fig.savefig(filename)
        logger.info("Created figure {}".format(filename))

    if kwargs.pop("__return_result", False):
        return (model, data, metadata, theta)

    # Write the result to file.
    _write_output(_prefix(args, "estimate.pkl"), metadata)
    return None