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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 main(**kwargs):
 """ Draw a couple of simple graphs and optionally generate an HTML file to upload them """

    draw_lines()
    draw_histogram()
    draw_bar_chart()
    destination = "-r /report"
    if use_html:
        generate_html()
        command = "dx-build-report-html {h} {d}".format(h=html_filename, d=destination)
    else:
        command = "dx-build-report-html {l} {b} {h} {d}".format(l=lines_filename, b=bars_filename, h=histogram_filename, d=destination)
    sub_output = json.loads(subprocess.check_output(command, shell=True))
    output = {}
    output["report"] = dxpy.dxlink(sub_output["recordId"])
    return output