Block chain installer not working

Hi I am trying to install the new Verge lumos wallet and want to apply the blockchain.
When I open my terminal on my mac and put in the line as stated in the introduction, I get the following message: 
![image](https://user-images.githubusercontent.com/52580821/60739741-6402e200-9f63-11e9-9b15-34e1cededf5f.png)

How do I fix this?
