def _read_file(self, filename):
if self.__compression:<EOL><INDENT>f = gzip.GzipFile(filename, "<STR_LIT:rb>")<EOL><DEDENT>else:<EOL><INDENT>f = open(filename, "<STR_LIT:rb>")<EOL><DEDENT>res = pickle.load(f)<EOL>f.close()<EOL>return res<EOL>
read a Python object from a cache file.

Reads a pickled object from disk and returns it.

:param filename: Name of the file that should be read.
:type filename: str
:rtype: object