'Gets the line of text designated by the provided line number.
Arguments:
line_number: The line number of the line we want to find.
Returns:
The line of text designated by the provided line number.'

def line_number_to_line(self, line_number):

    start_index = self._line_start_indexes[(line_number - 1)]
    if (len(self._line_start_indexes) == line_number):
        line = self._string[start_index:]
    else:
        end_index = self._line_start_indexes[line_number]
        line = self._string[start_index:(end_index - 1)]
    return line
