class Logger

Logger#sev_threshold= is an alias for Logger#level=.

logger.level = :error # => :error
logger.level = 'error' # => "error"
logger.level = 3 # => 3
logger.level = Logger::ERROR # => 3

Argument +severity+ may be an integer, a string, or a symbol:

See {Log Level}[rdoc-ref:Logger@Log+Level].
Sets the log level; returns +severity+.

def level=(severity)
  @level = Severity.coerce(severity)
end