I am trying to build my own PDF Export for a Pivot View using a Wizard in Odoo 13. I tried to follow this Tutorial (for Odoo 12): https://speedysense.com/create-custom-report-odoo-12/ 
and got stuck.

In my Wizard, I have a method _get report(), defining the data to be reportedn and then calling 

self.env.ref('module.feature_report').report_action(self, data)

In the Wizard's view, I defined the report 

<report id="module.feature_report"

And there is also an abstract class ReportView called

_name = 'report.module.feature_report_view'

Now when I try to start the odoo server and update the module, I get an AssertionError: The ID "module.feature_report" refers to an uninstalled module.

I googled the error and found this: https://www.odoo.com/de_DE/forum/hilfe-1/question/refers-to-an-uninstalled-module-122234

So I tried to replace the . with a _ in all 3 files (module_feature_report) and I was able to start the odoo server. But when I try to report, I get the following Error: ValueError: not enough values to unpack (expected 2, got 1)
and found this solution: https://stackoverflow.com/questions/51770510/valueerror-not-enough-values-to-unpack-expected-2-got-1-odoo-11-costum-repor
whicht leads to the first Error again...

Can anyone help me?