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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 set(self, value, start=None, stop=None):
 		"""Set the range from start to stop to value."""

		_check_start_stop(start, stop)
		# start_index, stop_index will denote the sections we are replacing
		start_index = self._bisect_left(start)
		if start is not None:  # start_index == 0
			prev_value = self._values[start_index - 1]
			if prev_value == value:
				# We're setting a range where the left range has the same
				# value, so create one big range
				start_index -= 1
				start = self._keys[start_index]
		if stop is None:
			new_keys = [start]
			new_values = [value]
			stop_index = len(self._keys)
		else:
			stop_index = self._bisect_right(stop)
			stop_value = self._values[stop_index - 1]
			stop_key = self._keys[stop_index - 1]
			if stop_key == stop and stop_value == value:
				new_keys = [start]
				new_values = [value]
			else:
				new_keys = [start, stop]
				new_values = [value, stop_value]
		self._keys[start_index:stop_index] = new_keys
		self._values[start_index:stop_index] = new_values