code: def test_single_group():
      """Ensures error is raised when attempting to conduct SA on a single group."""
      sp = ProblemSpec(
          {
              "names": ["x1"],
              "bounds": [[-1, 1]],
              "groups": ["G1"],
              "outputs": ["Y"],
          }
      )
  
      def func(X):
          return X[1] * X[0]
  
      sp.sample_latin(50)
      sp.evaluate(func)
  
      with pytest.raises(ValueError):
          sp.analyze_hdmr()
  
file_path: SALib/tests/test_problem_spec.py
imports: import pytest
  import copy
  import numpy
  import pandas
  from SALib import ProblemSpec
  from SALib.test_functions import Ishigami
label_desc: Use image node_id 7 for calling a global function with example usage: test_single_group() and returns: unknown