Python started to support async/await syntax in version 3.7.
We want to explore how to support this in OpenTelemetry Python.
Things to be explored are:

1. Do we provide this in the API package or API+SDK?
2. How do we test? If test cases are written using the async/await syntax, they won't work in Python <= v3.6, we might need to collect test cases based on runtime version.