To find the function definition related nodes, I will look at the higher level nodes. Hence, I can see that the 'function' nodes with ids = [1, 17], and 'lhs' nodes with ids = [2, 18], represent definition of functions in the code. Incorporating each of these nodes, I can make a general rule to extract the definitions.

This python script can be executed:

```py
# we see that the function name is the first keyword, hence we get the snippet at the start.
temp_0 = code_snippet.strip()
# as our required function name, from the snippet is the first one in this string, we split and get the first snippet, which is our function.
extracted = temp_0.split(' ')[0].strip()
```

This script will extract the function name 'one-not-even' from the given code snippet.