code: def test_student_t(
      x: float, mean: float, scale: float, df: int
  ) -> None:
      cast = to_default_float
      gpf = logdensities.student_t(
          cast(x), cast(mean), cast(scale), df
      ).numpy()
      sps = scipy.stats.t(df=df, loc=mean, scale=scale).logpdf(x)
      np.testing.assert_allclose(gpf, sps)
  
file_path: GPflow/tests/gpflow/test_logdensities.py
imports: import numpy
  import pytest
  import scipy.stats
  from numpy.random import randn
  from numpy.testing import assert_allclose
  from scipy.stats import multivariate_normal
  from gpflow import logdensities
  from gpflow.base import AnyNDArray
  from gpflow.utilities import to_default_float
label_desc: Use image node_id 7 for calling a global function with example usage: test_student_t(x, mean, scale, df) without return types