class Puma::LogWriter

def initialize(stdout, stderr, env: ENV)

Create a LogWriter that prints to +stdout+ and +stderr+. 
def initialize(stdout, stderr, env: ENV)
  @formatter = DefaultFormatter.new
  @custom_logger = nil
  @stdout = stdout
  @stderr = stderr
  @debug = env.key?('PUMA_DEBUG')
  @error_logger = ErrorLogger.new(@stderr, env: env)
end