I confirmed an error due to variable name pollution during the process of automatically finding tokens in the googletrans package, which I tried to use to support various languages. Therefore, I will keep version 0.1.9 as a development version and revert back to version 0.1.8. For those considering support for various languages, please refer to version 0.1.9.
Version 0.1.10 is the same as version 0.1.8.