Get status of radiobuttons and checkboxes?

[Rapid1898-code]

Hello - i try to get the status (checked / unchecked) of the radiobuttons and checkboxes in this document.

I tried it with the following code but I always get a None return

Example

from PyPDF2 import PdfReader

reader = PdfReader ("input.pdf")
fields = reader.get_fields()    
print(fields)

Find attached the pdf-file i want to read: input.pdf

Is it possible to get this information for the radio buttons and check boxes?