Not sure that's really the module you want to use if all you want to do is modify a single existing file. I've never used File::Tasks, but based on the documentation, it's probably overly complicated for what you are talking about, and all the edit operation does is overwrite the entire file. If all you need to do is append to the hosts file IO::File is the standard way. If you need random access to the lines in your hosts file, Tie::File is a good choice.
Is there a particular reason you want to use File::Tasks::Edit over a more typical solution?