3. There are $\mathbf{A}, \mathbf{B}, \mathbf{C}, \mathbf{D}, \mathbf{E}$ five people, each of whom always tells lies or always tells the truth, and they all know each other's behavior. $\mathrm{A}$ says $\mathrm{B}$ is a liar, $\mathrm{B}$ says $\mathrm{C}$ is a liar, $\mathrm{C}$ says $\mathrm{D}$ is a liar, $\mathrm{D}$ says $\mathbf{E}$ is a liar. Then, among these five people, what is the maximum number of liars?