naturally equivalent functors in Cat infinity

Let \(\mathcal{C}, \mathcal{D}\) be quasicategories and \(\mathcal{F},\mathcal{F}': \mathcal{C} \rightarrow \mathcal{D}\) be quasicategories. Then \(\mathcal{F}, \mathcal{F}'\) are said to be naturally equivalent, if they are equivalent 1-simplices in quasi category of quasi categories