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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 render_default(path, cp):
 """ This is the default function that will render a template to a string of HTML. The string will be for a drop-down tab that contains a link to the file. If the file extension requires information to be read, then that is passed to the content variable (eg. a segmentlistdict). """


    # define filename and slug from path
    filename = os.path.basename(path)
    slug = filename.replace('.', '_')

    # initializations
    content = None

    if path.endswith('.xml') or path.endswith('.xml.gz'):
        # segment or veto file return a segmentslistdict instance
        try:
            wf_file = SegFile.from_segment_xml(path)
            # FIXME: This is a dictionary, but the code wants a segmentlist
            #        for now I just coalesce.
            wf_file.return_union_seglist()
        except Exception as e:
            print('No segment table found in %s : %s' % (path, e))

    # render template
    template_dir = pycbc.results.__path__[0] + '/templates/files'
    env = Environment(loader=FileSystemLoader(template_dir))
    env.globals.update(abs=abs)
    env.globals.update(open=open)
    env.globals.update(path_exists=os.path.exists)
    template = env.get_template('file_default.html')
    context = {'path'     : path,
               'filename' : filename,
               'slug'     : slug,
               'cp'       : cp,
               'content'  : content}
    output = template.render(context)

    return output