Cryptograpy==2.3 requirement makes library incompatible with Python=3.8

[pleepleus]

cryptography version 2.3 has the following Python versioning requirement:

cryptography==2.3 -> python[version='>=2.7,<2.8.0a0|>=3.5,<3.6.0a0|>=3.7,<3.8.0a0|>=3.6,<3.7.0a0']

Which is not compatible with Python >=3.8.