How do I install Psychotoolbox into matlab?

I am currently installing psychotoolbox into my mac laptop. I keep recieving the following error messages:

svn: error: The subversion command line tools are no longer provided by Xcode.

Sorry, the download command "CHECKOUT" failed with error code 72:

svn: error: The subversion command line tools are no longer provided by Xcode.

I however do have svn installed onto my computer under the /usr/bin directory and am able to use svn commands in the terminal.

I am installing as directed by opening matlab navigating to the directory the Downloadpsychotoolox.m is in and running it.