[issue20923] [doc] Explain ConfigParser 'valid section name' and .SECTCRE

[miss-islington]

Change by miss-islington <mariatta.wijaya+miss-islington at gmail.com>:


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pull_requests: +29634
pull_request: https://github.com/python/cpython/pull/31507

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue20923>
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