I do it so.
import requests
import json
session = requests.Session()
session.auth = ('name', 'pass')
headers = {'content-type': 'application/json'}
page = {"space": "~spacekey", 'title': 'title', 'content': 'content', "parentId": 1234567}
payload = json.dumps({"jsonrpc" : "2.0", "method": "storePage", "params": [page], "id": 1})
response = session.post('https://example.com/rpc/json-rpc/confluenceservice-v2', headers=headers, data=payload)
But that's not enough. I need to create a page using a template. Using 'templateId=123456789'