Created functions to draw a triangle and a rect.

- It's like a variable in that you reference it by name
- Functions break routines up into subprocesses; think recursion. Quick sort
is a perfect example of this.

shapes.py

@@ -5,7 +5,19 @@
 from turtle import *
 
 def triangle(side_length):
-    pass
+    forward(side_length)
+    right(120)
+    forward(side_length)
+    right(120)
+    forward(side_length)
+    right(120)
 
 def rectangle(height, width):
-    pass
+    forward(width)
+    right(90)
+    forward(height)
+    right(90)
+    forward(width)
+    right(90)
+    forward(height)
+    right(90)