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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 escape(html, force=False):
 """Returns the given HTML with ampersands, quotes and angle brackets encoded."""

    if hasattr(html, '__html__') and not force:
        return html
    if html in NOTHING:
        return ''
    else:
        return to_string(html).replace('&', '&amp;').replace(
            '<', '&lt;').replace('>', '&gt;').replace("'", '&#39;').replace(
            '"', '&quot;')