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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 _iter_blocks(self):
 """Iter input lines in blocks separated by blank lines."""

        lines = []
        for line in self._iter_unfolded_lines():
            if line:
                lines.append(line)
            elif lines:
                self.records_read += 1
                yield lines
                lines = []
        if lines:
            self.records_read += 1
            yield lines