look for pressure_at_sealevel in http://api.luftdaten.info/static/v1/data.json

luftdaten.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

"""
license CC BY-SA 3.0
http://creativecommons.org/licenses/by-sa/3.0/deed.de
"""

import datetime
import json
import requests

print('Start')
def requestWeb():
    r = requests.get('http://api.luftdaten.info/static/v1/data.json')
    with open('data.json', 'wb') as json_file:
        json_file.writelines(r)
    print('Daten heruntergeladen und als data.json gespeichert')
    return r.json()
    
try:
    with open('data.json') as json_file: 
        luftdaten = json.load(json_file)
except FileNotFoundError:
    print("Datei nicht gefunden, neue Daten werden heruntergeladen!")
    luftdaten = requestWeb()
timestamp = datetime.datetime.strptime(luftdaten[0]['timestamp'], "%Y-%m-%d %H:%M:%S")
difference = datetime.datetime.now()-timestamp
if ((difference.days * 24 * 60 * 60) + difference.seconds) > (6 * 60 * 60):
    print("Zeitstempel alt {}, neue Daten werden heruntergeladen!".format(difference))
    luftdaten = requestWeb()
timestamp = datetime.datetime.strptime(luftdaten[0]['timestamp'], "%Y-%m-%d %H:%M:%S")
for id in luftdaten:
    foundPressure = False
    if (48.5 < float(id['location']['latitude']) < 49 
             and 10.0 < float(id['location']['longitude']) < 10.2):
        for sensordata in id["sensordatavalues"]:
            if sensordata["value_type"] == 'pressure_at_sealevel':
                 foundPressure = True
    if foundPressure:
        place = 'lat={:6.3f}, lon={:6.3f}, alt={:4.1f}'.format(
             float(id['location']['latitude']),
             float(id['location']['longitude']),
             float(id['location']['altitude']))
        time ='{}'.format(id['timestamp'])
        print('ID:{:5} {}'.format( 
             id['sensor']['id'], place))
        for sensordata in id["sensordatavalues"]:         
            if sensordata["value_type"] == 'temperature':
                print('Temperatur         {:8.1f}°C'.format(
                    float(sensordata['value'])))               
            if sensordata["value_type"] == 'pressure' and False:
                print('Luftdruck gemessen {:9.2f}'.format(
                    float(sensordata['value'])/100))
            if sensordata["value_type"] == 'pressure_at_sealevel':
                print('Luftdruck Meerhöhe {:9.2f}'.format(
                    float(sensordata['value'])/100))
                last = id
            if sensordata["value_type"] == 'humidity':
                print('Luftfeuchte        {:8.1f}%'.format(
                    float(sensordata['value'])))
print('##########')
print(last)
print('Daten von {}'.format(timestamp))