v1.6.4

• 🐛 Fix crash on Appveyor during nuget install due to old system CA
  certificates. We now use certifi's CA certs to download files. (#455)

v1.6.3

• 🐛 Fix missing SSL certificates on macOS (#447)
• 🛠 Update OpenSSL Python 3.5 patch to 1.1.1h on macOS (#449)

v1.6.2

• ✨ Python 3.9 updated to the final release version - v3.9.0 (#440)
• 🛠 Pypy updated to v7.3.2, adding alpha support for Python 3.7 (#430)