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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 get_caption_comments(content):
 """Retrieve an id and a caption from a code cell. If the code cell content begins with a commented block that looks like ## fig:id # multi-line or single-line # caption then the 'fig:id' and the caption will be returned. The '#' are stripped. """


    if not content.startswith('## fig:'):
        return None, None

    content = content.splitlines()

    id = content[0].strip('## ')

    caption = []
    for line in content[1:]:
        if not line.startswith('# ') or line.startswith('##'):
            break
        else:
            caption.append(line.lstrip('# ').rstrip())

    # add " around the caption. TODO: consider doing this upstream
    # in pandoc-attributes
    caption = '"' + ' '.join(caption) + '"'
    return id, caption