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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 easybake(css_in, html_in=sys.stdin, html_out=sys.stdout, last_step=None, coverage_file=None, use_repeatable_ids=False):
 """Process the given HTML file stream with the css stream."""

    html_doc = etree.parse(html_in)
    oven = Oven(css_in, use_repeatable_ids)
    oven.bake(html_doc, last_step)

    # serialize out HTML
    print(etree.tostring(html_doc, method="xml").decode('utf-8'),
          file=html_out)

    # generate CSS coverage_file file
    if coverage_file:
        print('SF:{}'.format(css_in.name), file=coverage_file)
        print(oven.get_coverage_report(), file=coverage_file)
        print('end_of_record', file=coverage_file)