Fix typo in docstring of matplotlib.colors.from_levels_and_colors

Author: Artyom Romanov

lib/matplotlib/colors.py

@@ -2757,8 +2757,8 @@ def from_levels_and_colors(levels, colors, extend='neither'):
 
     Returns
     -------
-    cmap : `~matplotlib.colors.Normalize`
-    norm : `~matplotlib.colors.Colormap`
+    cmap : `~matplotlib.colors.Colormap`
+    norm : `~matplotlib.colors.Normalize`
     """
     slice_map = {
         'both': slice(1, -1),