# File lib/memcache.rb, line 136
  def set(key, value, opts = {})
    opts = compatible_opts(opts)
    key  = key.to_s
    backup.set(key, value, opts) if backup

    expiry = opts[:expiry] || default_expiry
    flags  = opts[:flags]  || 0
    data   = marshal(value, opts)
    server(key).set(key, data, expiry, flags)
    value
  end