The concrete message from Pants is this:

./pants dependencies my-project/model/orm/project.py
10:41:59.97 [WARN] Pants cannot infer owners for the following imports in the target my-project/model/orm/project.py:
  * sqlalchemy (line: 7)
  * sqlalchemy.Column (line: 10)
  * sqlalchemy.ForeignKey (line: 10)
  * sqlalchemy.Integer (line: 10)
  * sqlalchemy.exc.IntegrityError (line: 11)
  * sqlalchemy.ext.hybrid.hybrid_property (line: 12)
  * sqlalchemy.orm.relationship (line: 13)
  * sqlalchemy_json.NestedMutableJson (line: 14)

I just found the issue, just read diagonally the docs and copied

target@

verbatim 🙈 instead of using the name of my target

Well, I’m still having an issue with this particular lib

pycryptodomex==3.6.6

which installs the package

Cryptodome

but Pants cannot infer it. I’m trying to tell Pants to not infer it:

# in my project.py file

import Cryptodome.Random # pants: no-infer-dep

and then adding the dependency explicitly to my root BUILD

# top BUILD file

python_sources(
  requirements=["//myproject:reqs#pycryptodomex"]
)

python_requirements(name="reqs")

But seems to have no effect (the dep is ignored but I can’t see it in the output of

./pants dependencies myproject/model/orm/project.py

If the name of the package isn’t same as what you use when importing the package you need to use something called module mapping https://www.pantsbuild.org/docs/python-third-party-dependencies#use-modules-and-module_mapping-when-the-module-name-is-not-standard

thanks @refined-addition-53644 that worked!