code: def test_rvs_scalar(distname, arg):
      # rvs should return a scalar when given scalar arguments (gh-12428)
      try:
          distfn = getattr(stats, distname)
      except TypeError:
          distfn = distname
          distname = "rv_histogram_instance"
  
      assert np.isscalar(distfn.rvs(*arg))
      assert np.isscalar(distfn.rvs(*arg, size=()))
      assert np.isscalar(distfn.rvs(*arg, size=None))
  
imports: import sys
  import numpy
  import numpy.testing
  import pytest
  from pytest import raises
  from scipy.integrate import IntegrationWarning
  import itertools
  from scipy import stats
  from .common_tests import check_normalization, check_moment, check_mean_expect, check_var_expect, check_skew_expect, check_kurt_expect, check_entropy, check_private_entropy, check_entropy_vect_scale, check_edge_support, check_named_args, check_random_state_property, check_meth_dtype, check_ppf_dtype, check_cmplx_deriv, check_pickling, check_rvs_broadcast, check_freezing, check_munp_expect
  from scipy.stats._distr_params import distcont
  from scipy.stats._distn_infrastructure import rv_continuous_frozen
label_desc: Use image node_id 3 for calling a global function with example usage: test_rvs_scalar(distname, arg) without return types