How to get management groups and subscriptions from different AAD tenant?

Thanks @juunas for pointing out what this question really need and @Joy Wang provide an API solution to get tenant list by account.

API solution

Thanks @juunas again, by using Tenants - List API we can easily listing tenants. (For more detail please take a look at his answer.)

I think it is a great general way to solve this question.

Azure SDK for Python solution

Fortunately, I found Azure SDK for Python have provide SubscriptionClient which allow me to list tenants programmatic.

This is how I list tenants in Python:

def get_tenants() -> [TenantIdDescription]:
    credentials = UserPassCredentials(
        'account',
        'password',
    )
    sub_client = SubscriptionClient(credentials)
    tenants = sub_client.tenants.list()
    return tenants

Combine SubscriptionClient into origin code

from azure.mgmt.managementgroups import ManagementGroupsAPI
from azure.mgmt.resource import SubscriptionClient
from msrestazure.azure_active_directory import UserPassCredentials

azure_account = ''
azure_pwd = ''

def get_credential(tenant_id: str = None):
    if tenant_id:
        return UserPassCredentials(
            azure_account,
            azure_pwd,
            tenant=tenant_id
        )
    else:
        return UserPassCredentials(
            azure_account,
            azure_pwd,
        )


def get_entities(tenant_id=None):
    credentials = get_credential(tenant_id)

    mgmt_groups_api = ManagementGroupsAPI(credentials)
    entities = mgmt_groups_api.entities.list()
    entity_infos = [entity for entity in entities]
    entity_names = [entity.display_name for entity in entity_infos]
    print(f'    entities: {entity_names}')


def get_tenants():
    credentials = get_credential()
    sub_client = SubscriptionClient(credentials)
    tenants = sub_client.tenants.list()
    return tenants


def main():
    tenants = get_tenants()

    i = 0
    print('[tenant list]')
    for tenant in tenants:
        print(f'tenant {i}:')
        print(f'    name:     {tenant.display_name}')
        print(f'    id:       {tenant.tenant_id}')
        get_entities(tenant.tenant_id)
        print()
        i = i + 1


if __name__ == '__main__':
    main()

output

[tenant list]
tenant 0:
    name:     tenant1
    id:       00000000-0000-0000-0000-000000000000
    entities: ['Tenant Root Group', 'group A', 'subGroup B', 'Microsoft Partner Network', 'subscription 2']

tenant 1:
    name:     tenant2
    id:       00000000-0000-0000-0000-000000000000
    entities: ['Tenant Root Group', 'subscription 3']

I think @juunas's comment is correct, you need to specify the tenant when you use the credential.

I think the problem becomes 'how to get a list of AAD tenant id'

You could use this REST API - Tenants - List to get the tenants for your account.

GET https://management.azure.com/tenants?api-version=2020-01-01

After getting the tenant id, specify the tenant in the user credential, make sure you used a work account without MFA(organization account, not personal account), the user credential uses the ROPC flow which will not work with personal account.