Explanation
"The current implementation of Terraform import can only import resources into the state. It does not generate
configuration. A future version of Terraform will also generate configuration. Because of this, prior to running
terraform import it is necessary to write manually a resource configuration block for the resource, to which the
imported object will be mapped. While this may seem tedious, it still gives Terraform users an avenue for
importing existing resources." https://www.terraform.io/cli/import/usage