handlers.py 文件源码

def _import_sendfile():
    # By default attempt to use os.sendfile introduced in Python 3.3:
    # http://bugs.python.org/issue10882
    # ...otherwise fallback on using third-party pysendfile module:
    # https://github.com/giampaolo/pysendfile/
    if os.name == 'posix':
        try:
            return os.sendfile  # py >= 3.3
        except AttributeError:
            try:
                import sendfile as sf
                # dirty hack to detect whether old 1.2.4 version is installed
                if hasattr(sf, 'has_sf_hdtr'):
                    raise ImportError
                return sf.sendfile
            except ImportError:
                pass