<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def lines(self):
 """List of file lines."""

        if self._lines is None:
            with io.open(self.path, 'r', encoding='utf-8') as fh:
                self._lines = fh.read().split('\n')

        return self._lines