How to properly divide words into groups?

Question

Clustering

In the test, you need to algorithmically show: How exactly can you
create
3
clusters of
words
similar in spelling from the following list of
words
:

The "weight" of each word before clustering must be unique.
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PS: without the use of ready-made libraries and built-in functions of the programming language, if the answer is presented in the form of code.