code: function (command) {
      command.option('--opensslbin <file>',
        'Location of the OpenSSL executable that the command uses. If not ' +
        'specified, the command attempts to find an OpenSSL executable in ' +
        'the current environment path.')
      command.option('-s, --san [value]',
        'add Subject Alternative Name(s) to the CSR', sanOption, [])
      command.option('-P, --passphrase [pass]',
        'Password for the private key. If specified with no value, prompts ' +
        'for the value.')
      Object.keys(pki.SUBJECT_ATTRIBUTES).forEach(function (key) {
        var attributeInfo = pki.SUBJECT_ATTRIBUTES[key]
        var optionName = fieldAsOption(key)
        var optionValue = attributeInfo.optionValue || optionName.toLowerCase()
        command.option('--' + fieldAsOption(key) + ' <' + optionValue + '>',
          attributeInfo.description)
      })
      return command
    }
docs: Appends options related to the use of PKI utilities to a Commander-based
  command.
  @param {Command} command - The Commander command to append options
  onto.
  @returns {Command}