yandex.locator API "Specify xml or json param" error, how to fix?

Question

Python

I'm trying to generate a request in accordance with https://tech.yandex.ru/locator/doc/dg/api/capture-... in python using the requests docs.python-requests.org/en/latest/ module. I tried everything, I always get an error: Specify xml or json param.
Has anyone experienced something similar? What could be the problem?
Errors in syntax and application of the requests module are excluded.
Code:

Error:

Answer 1

It says "Specify xml or json param"
Add the response data format to the request.

Answer 2

Also scratched my head. It turns out everything is very simple.

requests.post(url=url, headers=headers, data="json=" + data)

Answer 3

Roman Kitaev I'm trying, I specify the format in the headers. Here is the code:
here is the message: