Made function to count people who like a color.

friend_functions.py

@@ -72,7 +72,7 @@ def count_people_who_like_color(people, color):
         >>> count_people_who_like_color(family, "orange")
         1
     """
-    raise NotImplementedError()
+    return len(people_who_like_color(people, color))
 
 def get_color_dict(people):
     """Returns a dict showing how many people like each color.