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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 sanitize(url, config):
 """ Obtains dump of MySQL database by executing `mysqldump` command and sanitizes it output. :param url: URL to the database which is going to be sanitized, parsed by Python's URL parser. :type url: urllib.urlparse.ParseResult :param config: Optional sanitizer configuration to be used for sanitation of the values stored in the database. :type config: database_sanitizer.config.Configuration|None """

    if url.scheme != "mysql":
        raise ValueError("Unsupported database type: '%s'" % (url.scheme,))

    args, env = get_mysqldump_args_and_env_from_url(url=url)

    process = subprocess.Popen(
        args=["mysqldump"] + args,
        env=env,
        stdout=subprocess.PIPE,
    )

    return sanitize_from_stream(stream=process.stdout, config=config)