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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 generalize_sql(sql):
 """ Removes most variables from an SQL query and replaces them with X or N for numbers. Based on Mediawiki's DatabaseBase::generalizeSQL :type sql str|None :rtype: str """

    if sql is None:
        return None

    # multiple spaces
    sql = re.sub(r'\s{2,}', ' ', sql)

    # MW comments
    # e.g. /* CategoryDataService::getMostVisited N.N.N.N */
    sql = remove_comments_from_sql(sql)

    # handle LIKE statements
    sql = normalize_likes(sql)

    sql = re.sub(r"\\\\", '', sql)
    sql = re.sub(r"\\'", '', sql)
    sql = re.sub(r'\\"', '', sql)
    sql = re.sub(r"'[^\']*'", 'X', sql)
    sql = re.sub(r'"[^\"]*"', 'X', sql)

    # All newlines, tabs, etc replaced by single space
    sql = re.sub(r'\s+', ' ', sql)

    # All numbers => N
    sql = re.sub(r'-?[0-9]+', 'N', sql)

    # WHERE foo IN ('880987','882618','708228','522330')
    sql = re.sub(r' (IN|VALUES)\s*\([^,]+,[^)]+\)', ' \\1 (XYZ)', sql, flags=re.IGNORECASE)

    return sql.strip()