code: def test_automatic_t2F_conversion():
      effect = np.ones((5, 3))
      variance = np.ones(5)
      contrast = Contrast(effect, variance, stat_type="t")
      assert contrast.stat_type == "F"
  
imports: import numpy
  import pytest
  import scipy.stats
  from numpy.testing import assert_almost_equal
  from sklearn.datasets import make_regression
  from sklearn.linear_model import LinearRegression
  from nilearn.glm.contrasts import Contrast, _compute_fixed_effects_params, compute_contrast, compute_fixed_effect_contrast, expression_to_contrast_vector
  from nilearn.glm.first_level import run_glm
label_desc: Use image node_id 17 for calling a global function with example usage: test_automatic_t2F_conversion() without return types