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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 run(url, output, config):
 """ Extracts database dump from given database URL and outputs sanitized copy of it into given stream. :param url: URL to the database which is to be sanitized. :type url: str :param output: Stream where sanitized copy of the database dump will be written into. :type output: file :param config: Optional sanitizer configuration to be used for sanitation of the values stored in the database. :type config: database_sanitizer.config.Configuration|None """

    parsed_url = urlparse.urlparse(url)
    db_module_path = SUPPORTED_DATABASE_MODULES.get(parsed_url.scheme)
    if not db_module_path:
        raise ValueError("Unsupported database scheme: '%s'" % (parsed_url.scheme,))
    db_module = importlib.import_module(db_module_path)
    session.reset()
    for line in db_module.sanitize(url=parsed_url, config=config):
        output.write(line + "\n")