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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _read_cache_from_file(self):
 """Read the contents of the cache from a file on disk."""

        cache = {}
        try:
            with(open(self._cache_file_name, 'r')) as fp:
                contents = fp.read()
                cache = simplejson.loads(contents)
        except (IOError, JSONDecodeError):
            # The file could not be read. This is not a problem if the file does not exist.
            pass

        return cache