code: function status (code) {
    if (typeof code === 'number') {
      if (!status[code]) throw new Error('invalid status code: ' + code)
      return code
    }
  
    if (typeof code !== 'string') {
      throw new TypeError('code must be a number or string')
    }
  
    // '403'
    var n = parseInt(code, 10)
    if (!isNaN(n)) {
      if (!status[n]) throw new Error('invalid status code: ' + n)
      return n
    }
  
    n = status[code.toLowerCase()]
    if (!n) throw new Error('invalid status message: "' + code + '"')
    return n
  }
docs: Get the status code.
  
  Given a number, this will throw if it is not a known status
  code, otherwise the code will be returned. Given a string,
  the string will be parsed for a number and return the code
  if valid, otherwise will lookup the code assuming this is
  the status message.
  
  @param {string|number} code
  @returns {number}
  @public