'\b' doesn't work in regex

Hello, looks like this code:

re.search("\b[a-z]{2,}\b", "My name is ...", re.I)

doesn't return correct result (the problem is in '\b' patterns). But this regex works fine in testing environment, for example https://www.regex101.com/

Could you take a look on this issue? Maybe my mistake but we should check it...

From: http://www.checkio.org/mission/striped-words/solve/

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