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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 preformatted_text(source: str) -> str: """Renders preformatted text box"""

    environ.abort_thread()

    if not source:
        return ''

    source = render_utils.html_escape(source)

    return '<pre class="preformatted-textbox">{text}</pre>'.format(
        text=str(textwrap.dedent(source))
    )