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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 line_range(self, line_number):
 """Return a slice for the given line number"""

    if line_number <= 0 or line_number > len(self.lines):
      raise IndexError('NOTE: Python file line numbers are offset by 1.')

    if line_number not in self.logical_lines:
      return slice(line_number, line_number + 1)
    else:
      start, stop, _ = self.logical_lines[line_number]
      return slice(start, stop)