code: def test_empty_es():
      es = EntitySet("es")
      assert es.id == "es"
      assert es.dataframe_dict == {}
      assert es.relationships == []
      assert es.time_type is None
  
imports: from datetime import datetime
  import numpy
  import pandas
  import pytest
  from woodwork.exceptions import TypeConversionError
  from woodwork.logical_types import Boolean, Categorical, Datetime, Double, Integer, NaturalLanguage
  from featuretools.entityset.entityset import LTI_COLUMN_NAME, EntitySet
  from featuretools.tests.testing_utils import to_pandas
  from featuretools.utils.gen_utils import Library, import_or_none, is_instance
label_desc: Use image node_id 1 for calling a global function with example usage: test_empty_es() without return types