Reverting https://github.com/yaml/pyyaml/pull/74 Revert "Make pyyaml safe by default." This reverts commit bbcf95fa051fdba9bbf879332e2f7999b195cf95. This reverts commit 7b68405c81db889f83c32846462b238ccae5be80. This reverts commit 517e83e8058e9d6850ab432ef22d84c2ac2bba5a.