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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 setup_logging(name):
 """Setup logging according to environment variables."""

    logger = logging.getLogger(__name__)
    if 'NVIM_PYTHON_LOG_FILE' in os.environ:
        prefix = os.environ['NVIM_PYTHON_LOG_FILE'].strip()
        major_version = sys.version_info[0]
        logfile = '{}_py{}_{}'.format(prefix, major_version, name)
        handler = logging.FileHandler(logfile, 'w', 'utf-8')
        handler.formatter = logging.Formatter(
            '%(asctime)s [%(levelname)s @ '
            '%(filename)s:%(funcName)s:%(lineno)s] %(process)s - %(message)s')
        logging.root.addHandler(handler)
        level = logging.INFO
        if 'NVIM_PYTHON_LOG_LEVEL' in os.environ:
            lvl = getattr(logging,
                          os.environ['NVIM_PYTHON_LOG_LEVEL'].strip(),
                          level)
            if isinstance(lvl, int):
                level = lvl
        logger.setLevel(level)