Error when attempting "brew cask install wch-ch34x-usb-serial-driver"

[jiva]

Here's the following error message:

 $ brew cask install wch-ch34x-usb-serial-driver
Error: Calling Hbc::DSL#license is disabled! There is no replacement.
Please report this to the decaturmakers/ch340_drivers-linux-mac-windows tap:
  /usr/local/Homebrew/Library/Taps/decaturmakers/homebrew-ch340_drivers-linux-mac-windows/Casks/wch-ch34x-usb-serial-driver.rb:9

Here's the version of brew I'm running:

$ brew --version
Homebrew 1.7.2
Homebrew/homebrew-core (git revision bc34; last commit 2018-09-02)

I guess the license directive is no longer supported but I don't know enough brew to suggest a replacement.