code: def reverse_axis(self, axis_to_reverse):
          
          if axis_to_reverse.lower() == 'x':
              self.general.reverse_x_axis = True
          if axis_to_reverse.lower() == 'y':
              self.general.reverse_y_axis = True
          if axis_to_reverse.lower() != 'x' or axis_to_reverse.lower() != 'y':
              raise ValueError('Axis for reversing needs to be either x or y.')
          return
docs: Reverse an axis in all figure plots.
  
          This will reverse the tick marks on an axis for each plot in the figure.
          It can be overridden in SinglePlot class.
  
          Args:
              axis_to_reverse (str): Axis to reverse. Supports `x` and `y`.
  
          Raises:
              ValueError: The string representing the axis to reverse is not `x` or `y`.