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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 get_index_line(self,lnum):
 """ Take the 1-indexed line number and return its index information"""

    if lnum < 1:
      sys.stderr.write("ERROR: line number should be greater than zero\n")
      sys.exit()
    elif lnum > len(self._lines):
      sys.stderr.write("ERROR: too far this line nuber is not in index\n")
      sys.exit()
    return self._lines[lnum-1]