code: def test_builder_to_backend_smoke(self, use_cpu_only, backend):
      t = np.array(
          [[[-1, 3, 6]], [[-1, 2, -3]], [[4, -5, 6]]], dtype=np.float32
      )
      input_placeholders = {"x": mb.placeholder(shape=t.shape)}
      input_values = {"x": t}
  
      def build(x):
          return mb.prelu(
              x=x, alpha=np.array([1, 2, 3], dtype=np.float32)
          )
  
      expected_output_types = (3, 1, 3, types.fp32)
      expected_outputs = np.array(
          [[[-1, 3, 6]], [[-2, 2, -6]], [[4, -15, 6]]], dtype=np.float32
      )
  
      run_compare_builder(
          build,
          input_placeholders,
          input_values,
          expected_output_types,
          expected_outputs,
          use_cpu_only=use_cpu_only,
          frontend_only=False,
          backend=backend,
      )
  
imports: from scipy import special
  import scipy
  from coremltools.converters.mil import testing_reqs
  from coremltools.converters.mil.testing_reqs import *
  from .testing_utils import run_compare_builder
label_desc: Use image node_id 1 for calling the TestPReLU obj's underlying member method code with example usage: obj.test_builder_to_backend_smoke(use_cpu_only, backend) and returns: mb