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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 _read_prm_file(prm_filename):
 """read the prm file"""

    logger.debug("Reading config-file: %s" % prm_filename)
    try:
        with open(prm_filename, "r") as config_file:
            prm_dict = yaml.load(config_file)
    except yaml.YAMLError:
        raise ConfigFileNotRead
    else:
        _update_prms(prm_dict)