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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(self):
 """Read virtualenv metadata from cache."""

        if os.path.exists(self.filepath):
            with open(self.filepath, 'rt', encoding='utf8') as fh:
                lines = [x.strip() for x in fh]
        else:
            logger.debug("Index not found, starting empty")
            lines = []
        return lines