[issue16510] Using appropriate checks in tests

[Serhiy Storchaka]

Changes by Serhiy Storchaka <storchaka at gmail.com>:


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dependencies: +Use specific asserts in array tests, Use specific asserts in datetime tests, Use specific asserts in http.cookiejar tests, Use specific asserts in weakref tests

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue16510>
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