Bug report: subnet-gce-int already exists

[glasnt]

╷
│ Error: Error creating Subnetwork: googleapi: Error 409: The resource 'projects/SomeProject/regions/us-central1/subnetworks/subnet-gce-int' already exists, alreadyExists
│
│   with module.dynamic-python-webapp.module.gce-vpc[0].module.subnets.google_compute_subnetwork.subnetwork["us-central1/subnet-gce-int"],
│   on .terraform/modules/dynamic-python-webapp.gce-vpc/modules/subnets/main.tf line 28, in resource "google_compute_subnetwork" "subnetwork":
│   28: resource "google_compute_subnetwork" "subnetwork" {

#56 (comment)

I thought subnets were unique to the network, but obviously not.