[3.7] bpo-33383: Fix crash in get() of the dbm.ndbm database object. (GH-6630)#6631

serhiy-storchaka merged 2 commits intopython:3.7python/cpython:3.7from

miss-islington:backport-2e38cc3-3.7miss-islington/cpython:backport-2e38cc3-3.7Copy head branch name to clipboard