Hi Kenneth, below is some code I wrote for getting all information about each network within a single org and putting that in a csv.
dashboard = meraki.DashboardAPI(key)
orgs = dashboard.organizations.getOrganizations()
org_id = 'xxx'
response = dashboard.organizations.getOrganizationNetworks(org_id)
# You should create a loop around this to cycle through every org (You'll need to read in the next org_id each time). You can do response.extend() to keep adding the info to the response variable. Then you can write all that info to a csv with the code below:
with open('networks.csv', 'w') as new_file:
csv_writer = csv.DictWriter(new_file, response[0].keys())
csv_writer.writeheader()
csv_writer.writerows(response)
Hope this helps, I'm sorry it isn't exactly what you were looking for. Why do you need all those network IDs anyway?