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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 clean_content(content):
 """\ Removes paragraph numbers, section delimiters, xxxx etc. from the content. This function can be used to clean-up the cable's content before it is processed by NLP tools or to create a search engine index. `content` The content of the cable. """

    for pattern, subst in _CLEAN_PATTERNS:
        content = pattern.sub(subst, content)
    return content