def build_package_data(self):
        """Copy data files into build directory"""
        for package, src_dir, build_dir, filenames in self.data_files:
            for filename in filenames:
                target = os.path.join(build_dir, filename)
                self.mkpath(os.path.dirname(target))
                self.copy_file(
                    os.path.join(src_dir, filename), target, preserve_mode=False
                )
Copy data files into build directory
product/gradle-plugin/src/main/python/setuptools/_distutils/command/build_py.py