How to use behave for project files testing?

I have created a python project, and want to write behaviour tests on top of it using behave. My project structure is like this:

- project root
--- features
------ test_feature1.feature
------ steps
--------- test_feature_step1.py
--- project directory
------ init.py
------ package1.py

I have to test the methods in package.py and so, need to import it in test_feature_step1.py. I don't know how to do that and was unable to find enough documentation on the same. So, how can this be implemented?