code: func (c *Context) WithDeadline(sec int64, nsec int64) *Context {
  	child, cancel := context.WithDeadline(c.context, time.Unix(sec, nsec))
  	return &Context{
  		context: child,
  		cancel:  cancel,
  	}
  }
docs: // WithDeadline returns a copy of the original context with the deadline adjusted
  // to be no later than the specified time.
  //
  // Canceling this context releases resources associated with it, so code should
  // call cancel as soon as the operations running in this Context complete.