cache.py 文件源码

def __init__(self):
        self.__index = None
        self.py_tag = 'cpython-%s%s' % sys.version_info[:2]
        """
        Short name for distinguish Python implementations and versions.

        It's like `sys.implementation.cache_tag` but for Python < 3.3
        we generate something similar.  See:
        http://docs.python.org/3/library/sys.html#sys.implementation

        .. todo:: Detect interpreter (e.g., PyPy).
        """