Environment details

• Programming language: python
• OS: linux
• Language runtime version: 3.8.8
• Package version: 1.0.0

Steps to reproduce

1. Use google-cloud-spanner 3.9.0 (3.12.0 is latest)
2. Do anything (e.g. SELECT) with python-spanner-alchemy
3. returns ModuleNotFoundError: No module named 'google.cloud.spanner_v1.data_types'

Steps to resolve:

Update google-cloud-spanner (3.12.0 works, I'm not sure what the minimal version required is)