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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_text(value, topic=False):
 """ Replaces "profane" words with more suitable ones. Uses bleach to strip all but whitelisted html. Converts bbcode to Markdown """

    for x in PROFANITY_REPLACEMENTS:
        value = value.replace(x[0], x[1])

    for bbset in BBCODE_REPLACEMENTS:
        p = re.compile(bbset[0], re.DOTALL)
        value = p.sub(bbset[1], value)

    bleached = bleach.clean(value, tags=ALLOWED_TAGS, attributes=ALLOWED_ATTRIBUTES, strip=True)

    # We want to retain markdown quotes and we'll be running bleach again in format_post.
    bleached = bleached.replace('&gt;', '>').replace('&amp;', '&')
    return bleached