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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 SetLines(self, lines):
 """Set number of screen lines. Args: lines: An int, number of lines. If None, use terminal dimensions. Raises: ValueError, TypeError: Not a valid integer representation. """


    (self._cli_lines, self._cli_cols) = TerminalSize()

    if lines:
      self._cli_lines = int(lines)