[feature request] Add lldb equivalent to Tools/gdb

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2019-11-11.17:25:55.190>
labels = ['type-feature']
title = '[feature request] Add lldb equivalent to Tools/gdb'
updated_at = <Date 2021-05-29.17:54:55.460>
user = 'https://github.com/Zheaoli'

bugs.python.org fields:

activity = <Date 2021-05-29.17:54:55.460>
actor = 'erlendaasland'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Demos and Tools']
creation = <Date 2019-11-11.17:25:55.190>
creator = 'Manjusaka'
dependencies = []
files = []
hgrepos = []
issue_num = 38768
keywords = []
message_count = 5.0
messages = ['356372', '393689', '393891', '394525', '394734']
nosy_count = 8.0
nosy_names = ['gregory.p.smith', 'ronaldoussoren', 'vstinner', 'ned.deily', 'corona10', 'Manjusaka', 'erlendaasland', 'shreyanavigyan']
pr_nums = []
priority = 'normal'
resolution = None
stage = 'needs patch'
status = 'open'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue38768'
versions = []