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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 parse_sphinx_docopts(index):
 """ Parse the Sphinx index for documentation options. Parameters index : str The Sphinx index page Returns ------- docopts : dict The documentation options from the page. """


    pos = index.find('var DOCUMENTATION_OPTIONS')
    if pos < 0:
        raise ValueError('Documentation options could not be found in index.')
    pos = index.find('{', pos)
    if pos < 0:
        raise ValueError('Documentation options could not be found in index.')
    endpos = index.find('};', pos)
    if endpos < 0:
        raise ValueError('Documentation options could not be found in index.')
    block = index[pos + 1:endpos].strip()
    docopts = {}
    for line in block.splitlines():
        key, value = line.split(':', 1)
        key = key.strip().strip('"')

        value = value.strip()
        if value[-1] == ',':
            value = value[:-1].rstrip()
        if value[0] in '"\'':
            value = value[1:-1]
        elif value == 'false':
            value = False
        elif value == 'true':
            value = True
        else:
            try:
                value = int(value)
            except ValueError:
                # In Sphinx 1.7.5, URL_ROOT is a JavaScript fragment.
                # Ignoring this entry since URL_ROOT is not used
                # elsewhere.
                # https://github.com/sphinx-gallery/sphinx-gallery/issues/382
                continue

        docopts[key] = value

    return docopts