def _check_compiler (self):
        # We do this late, and only on-demand, because this is an expensive
        # import.
        from distutils.ccompiler import CCompiler, new_compiler
        if not isinstance(self.compiler, CCompiler):
            self.compiler = new_compiler(compiler=self.compiler,
                                         dry_run=self.dry_run, force=1)
            customize_compiler(self.compiler)
            if self.include_dirs:
                self.compiler.set_include_dirs(self.include_dirs)
            if self.libraries:
                self.compiler.set_libraries(self.libraries)
            if self.library_dirs:
                self.compiler.set_library_dirs(self.library_dirs)
Check that 'self.compiler' really is a CCompiler object;
dataset/ETHPy150Open babble/babble/include/jython/Lib/distutils/command/config.py/config._check_compiler