This function takes a single string as an argument.

Hello, my cat. And my cat doesn't say "hello" back.

It returns a dictionary of words and their counts:

{'hello': 2, 'my': 2, 'cat': 2, 'and': 1, "doesn't": 1, 'say': 1, 'back': 1}

Case should be ignored. Output keys must be lowercase.

Key order in the dictionary doesn't matter.

Split the strings into words on any whitespace.

Ignore each of the following characters:

" : ; , . - + = / \ | [ ] { } ( ) * ^ &

If the input contains no ignored characters, return an empty dictionary.