Preferred way to install an external modules for a plugin?

[charlweed]

[Again, my apologies for previously posting this to the Sygil thread]

I'd like to write a plugin that uses PyDictionary, which is a english language dictionary.
How do I "install" external modules so they are available to my Calibre plugin, and can be re-distributed within the zip? I tried copying the module source into a directory of my module. It works in my IDE, but when I restart Calibre, my plugin will not load, and Calibre gives the error:

`ModuleNotFoundError: No module named 'PyDictionary'`

I'm a Python and Calibre plugin newb so I have lots of trial and error ahead. The goal of my plugin will be to help me un-mangle a very messy Calibre library. There are hundreds of books with titles mixed into the author fields, and vice-versa. My first pass is to find authors that have several common english words in the name. Then I can inspect them to see if they are really titles, and process them further.
I tried hunspell, becuase it seems it might be faster, but it seems to have compatibility issues, and has not been updated fro quite some time.

[kovidgoyal]

There are builtin dictionaries in calibre already use those. See the functions in spell/dictionary.py