code: def test_is_mutable(app_client):
      assert Database(app_client.ds, is_memory=True).is_mutable is True
      assert (
          Database(
              app_client.ds, is_memory=True, is_mutable=True
          ).is_mutable
          is True
      )
      assert (
          Database(
              app_client.ds, is_memory=True, is_mutable=False
          ).is_mutable
          is False
      )
  
file_path: datasette/tests/test_internals_database.py
imports: from datasette.app import Datasette
  from datasette.database import Database, Results, MultipleValues
  from datasette.utils.sqlite import sqlite3
  from datasette.utils import Column
  from .fixtures import app_client, app_client_two_attached_databases_crossdb_enabled
  import pytest
  import time
  import uuid
label_desc: Use image node_id 5 for calling a global function with example usage: test_is_mutable(app_client) without return types