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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 _extract_attrs(x, n):
 """Extracts attributes for an image. n is the index where the attributes begin. Extracted elements are deleted from the element list x. Attrs are returned in pandoc format. """

    try:
        return extract_attrs(x, n)

    except (ValueError, IndexError):

        if PANDOCVERSION < '1.16':
            # Look for attributes attached to the image path, as occurs with
            # image references for pandoc < 1.16 (pandoc-fignos Issue #14).
            # See http://pandoc.org/MANUAL.html#images for the syntax.
            # Note: This code does not handle the "optional title" for
            # image references (search for link_attributes in pandoc's docs).
            assert x[n-1]['t'] == 'Image'
            image = x[n-1]
            s = image['c'][-1][0]
            if '%20%7B' in s:
                path = s[:s.index('%20%7B')]
                attrs = unquote(s[s.index('%7B'):])
                image['c'][-1][0] = path  # Remove attr string from the path
                return PandocAttributes(attrs.strip(), 'markdown').to_pandoc()
        raise