# File lib/mongo/session.rb, line 132
    def initialize(server_session, client, options = {})
      @server_session = server_session
      options = options.dup

      # Because the read preference will need to be inserted into a command as a string, we convert
      # it from a symbol immediately upon receiving it.
      if options[:read_preference] && options[:read_preference][:mode]
        options[:read_preference][:mode] = options[:read_preference][:mode].to_s
      end

      @client = client.use(:admin)
      @options = options.freeze
      @cluster_time = nil
      @state = NO_TRANSACTION_STATE
    end