code: def _compile_to_sklearn(self, expr):
          
          sklearn_pipeline_str = generate_pipeline_code(expr_to_tree(expr, self._pset), self.operators)
          sklearn_pipeline = eval(sklearn_pipeline_str, self.operators_context)
          sklearn_pipeline.memory = self._memory
          return sklearn_pipeline
docs: Compile a DEAP pipeline into a sklearn pipeline.
  
          Parameters
          ----------
          expr: DEAP individual
              The DEAP pipeline to be compiled
  
          Returns
          -------
          sklearn_pipeline: sklearn.pipeline.Pipeline