web2py, how to use fetch instead of urllib.request? (for GAE) - google-app-engine

Question

I'm starting a project that must be deployed at the Google App Engine. I read that gluon.tools fetch function must be used instead of urllib.request.
Here I have two defs(), the first one runs ok with urllib, the second one with fetch doesn't run.
It looks as if data parameters has the wrong format.
How must be used this fetch function?
I've been looking for examples along the internet but I don't find anything (except the code of fetchfunction).
# -*- coding: utf-8 -*-
from gluon.tools import fetch
import json
import urllib
def gQLquery1():
data = {'query':'{me{username myMachines{name}}}'}
url = 'https://ecostruxure-machine-advisor.se.app/daas/graphql'
Bearer = "Bearer ngU5TkM5yN2m5VCBeJBQ4F3NGjuvecn8FqK7f7Fc"
data = json.dumps(data).encode('utf-8')
headers={'authorization': Bearer,'Content-Type':'application/json'}
req = urllib.request.Request(url, data=data)
req.add_header('authorization', Bearer)
req.add_header('Content-Type', 'application/json')
response = urllib.request.urlopen(req).read()
decoded = json.loads(response)
out = json.dumps(decoded)
return out
def gQLquery2():
data = {'query':'{me{username myMachines{name}}}'}
url = 'https://ecostruxure-machine-advisor.se.app/daas/graphql'
Bearer = "Bearer ngU5TkM5yN2m5VCBeJBQ4F3NGjuvecn8FqK7f7Fc"
#data = json.dumps(data).encode('utf-8')
headers={'authorization': Bearer,'Content-Type':'application/json'}
#req = urllib.request.Request(url, data=data)
#req.add_header('authorization', Bearer)
#req.add_header('Content-Type', 'application/json')
#response = urllib.request.urlopen(req).read()
response = fetch(url, data , headers )
decoded = json.loads(response)
out = json.dumps(decoded)
return out
ticket returned:
Versión
web2py™ Version 2.21.1-stable+timestamp.2020.11.28.04.10.44
Python Python 3.7.4: D:\Oscar\_Particular\web2py\web2py_no_console.exe (prefix: D:\Oscar\_Particular\web2py)
Traceback (most recent call last):
File "D:\Oscar\_Particular\web2py\gluon\tools.py", line 4639, in fetch
from google.appengine.api import urlfetch
File "D:\Oscar\_Particular\web2py\gluon\custom_import.py", line 85, in custom_importer
return base_importer(pname, globals, locals, fromlist, level)
ModuleNotFoundError: No module named 'applications.hola'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "D:\Oscar\_Particular\web2py\gluon\restricted.py", line 219, in restricted
exec(ccode, environment)
File "D:/Oscar/_Particular/web2py/applications/hola/controllers/default.py", line 126, in <module>
File "D:\Oscar\_Particular\web2py\gluon\globals.py", line 430, in <lambda>
self._caller = lambda f: f()
File "D:/Oscar/_Particular/web2py/applications/hola/controllers/default.py", line 94, in gQLquery2
response = fetch(url, data , headers )
File "D:\Oscar\_Particular\web2py\gluon\tools.py", line 4642, in fetch
html = urlopen(req).read()
File "urllib\request.py", line 222, in urlopen
File "urllib\request.py", line 523, in open
File "urllib\request.py", line 1247, in do_request_
TypeError: POST data should be bytes, an iterable of bytes, or a file object. It cannot be of type str.