Prefect 2.0: flow deployments using common package between flows

[giacomochiarella]

Hi everyone! I'm trying to get into Prefect 2.0 because we like and we want to use it. Great job first of all!
The point. As many flows share the same flow structure, it makes sense to have this task with some parameters in a common package.
Let's say I have a this tree:
dags

• prod
  • common
  • packageA
    • flowA
    • flowB
  • packageB
    • flowA
    • flowB
• staging
  • common
  • packageA
    • flowA
    • flowB
  • packageB
    • flowA
    • flowB

Problem. When I try to deploy:
cd dags/staging
prefect deployment build ./packageA/flowA.py:func -n name -t staging -i process -sb s3/staging
I get: ModuleNotFoundError: No module named 'staging' because in flowA I have import staging.common
I'm getting crazy to find out how it is supposed to deploy flows. It seems I should install the modules first but I wonder why the flow script is execute during the deployment. Even if I install the modules, not only flowA gets copied to s3, the whole folder where I run the command from gets copied.
Any suggestions?