code: def test_prior_str():
      # Tests __str__ method
      prior1 = bmb.Prior("Normal", mu=0, sigma=1)
      prior2 = bmb.Prior(
          "Normal", mu=0, sigma=bmb.Prior("HalfNormal", sigma=1)
      )
      assert str(prior1) == "Normal(mu: 0.0, sigma: 1.0)"
      assert (
          str(prior2)
          == "Normal(mu: 0.0, sigma: HalfNormal(sigma: 1.0))"
      )
      assert str(prior1) == repr(prior1)
  
imports: from os.path import dirname, join
  import pytest
  import numpy
  import pymc
  import pandas
  from scipy import special
  import bambi
label_desc: Use image node_id 9 for calling a global function with example usage: test_prior_str() without return types