[issue4751] Patch for better thread support in hashlib

[STINNER Victor]

STINNER Victor <victor.stinner at haypocalc.com> added the comment:

EVP_copy() and EVP_get_digest_size() should call 
ENTER_HASHLIB/LEAVE_HASHLIB to protect self->ctx.

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue4751>
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