Damn, it turned out all the same :) So I thought the snag was that the server administrator gave me the wrong address to send the request :( As a result, the server with the prefix / wsdl received a list of supported methods, including was specified and the address for the request.
But the program itself for the request:
import requests endpoint = "здесь адрес для запроса" body="""здесь запрос""" body = body.encode('utf-8') session = requests.session() session.headers = {"Content-Type": "text/xml; charset=utf-8"} session.headers.update({"Content-Length": str(len(body))}) response = session.post(url=endpoint, data=body, verify=False) print(response.content)