code: def test_scalar_and_mutable_sigma() -> None:
      param = par.Scalar(init=1.0, mutable_sigma=True).set_mutation(
          exponent=2.0, sigma=5
      )
      assert param.value == 1
      data = param.get_standardized_data(reference=param)
      assert data[0] == 0.0
      param.set_standardized_data(np.array([-0.2]))
      assert param.value == 0.5
      assert param.sigma.value == pytest.approx(5)
      param.mutate()
      assert param.sigma.value != pytest.approx(5)
      param.set_integer_casting()
      assert isinstance(param.value, int)
  
imports: import pickle
  import typing
  import pytest
  import numpy
  from nevergrad.common import errors
  from .None import parameter
label_desc: Use image node_id 10 for calling a global function with example usage: test_scalar_and_mutable_sigma() without return types