Implementing a verifier function to verify integrity of AST nodes

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2020-05-03.12:15:02.760>
labels = ['type-feature', 'library']
title = 'Implementing a verifier function to verify integrity of AST nodes'
updated_at = <Date 2020-05-03.12:15:12.688>
user = 'https://github.com/isidentical'

bugs.python.org fields:

activity = <Date 2020-05-03.12:15:12.688>
actor = 'BTaskaya'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2020-05-03.12:15:02.760>
creator = 'BTaskaya'
dependencies = ['39981']
files = []
hgrepos = []
issue_num = 40483
keywords = []
message_count = 1.0
messages = ['367969']
nosy_count = 3.0
nosy_names = ['serhiy.storchaka', 'pablogsal', 'BTaskaya']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue40483'
versions = []