def copy_file(self, source, target, preserve_mode=True):
        if source.endswith('.py') and not 'backport' in source:
            with open(source, 'rt') as input:
                nval = self.rtool.refactor_string(input.read(), source)
            with open(target, 'wt') as output:
                output.write(
                    'from __future__ import print_function, absolute_import\n')
                output.write('from contextlib import nested\n')
                output.write(str(nval))
        else:
            _build_py.copy_file(self, source, target,
                preserve_mode=preserve_mode)
dataset/ETHPy150Open tailhook/pyzza/setup.py/build_py26.copy_file/original