__init__.py 文件源码

def extraction_error(self):
        """Give an error message for problems extracting file(s)"""

        old_exc = sys.exc_info()[1]
        cache_path = self.extraction_path or get_default_cache()

        tmpl = textwrap.dedent("""
            Can't extract file(s) to egg cache

            The following error occurred while trying to extract file(s) to the Python egg
            cache:

              {old_exc}

            The Python egg cache directory is currently set to:

              {cache_path}

            Perhaps your account does not have write access to this directory?  You can
            change the cache directory by setting the PYTHON_EGG_CACHE environment
            variable to point to an accessible directory.
            """).lstrip()
        err = ExtractionError(tmpl.format(**locals()))
        err.manager = self
        err.cache_path = cache_path
        err.original_error = old_exc
        raise err