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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 set_default_log_levels(loggers_and_log_levels):
 """Set default log levels for some loggers. :param loggers_and_log_levels: List of tuple (logger name, level). """

    for logger, level in loggers_and_log_levels:
        if isinstance(level, str):
            level = level.upper()
        logging.getLogger(logger).setLevel(level)