problem with sending measurement values via the rest api

Concatenating strings like this is quite error prone.

I’d recommend first populating a Python dictionary, then encoding it as a JSON string using the json module. In your case, it could look like this:

import json

capability_alternate_id = "SENSOR_001"
sensor_alternate_id = "4711_CR_SENS"
measures = ["24.0", "99.0"]

body = {
        "capabilityAlternateId": capability_alternate_id,
        "measures": [measures],
        "sensorAlternateId": sensor_alternate_id
    }

json_body = json.dumps(body)

Here, we set Python variables for capability_alternate_id (a string), sensor_alternate_id (a string), and measures (an array of strings). We then define a dictionary (called body), and define keys and values in line with the format defined in your post above.

json.dumps(body) takes the Python object body, and converts it into JSON (using a process called serialisation).

This is preferred to editing a string directly — if you mess up defining body here, Python will throw an error that you can debug. When you manually concatenate a string together, Python will treat it like any other string, so it’s difficult to debug errors.