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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 _sync_with_file(self):
 """Clear in-memory structures so table is synced with the file."""

        self._records = []
        i = -1
        for i, line in self._enum_lines():
            self._records.append(None)
        self._last_synced_index = i