What is the syntax rule for having trailing commas in tuple definitions?

Question

In the case of a single element tuple, the trailing comma is required.

a = (\'foo\',)

What about a tuple with multiple elements? It seems t

Answer 1

Another advantage of trailing commas is that it makes diffs look nicer. If you started with

a = [
    1,
    2,
    3
]

and changed it to

a = [
    1,
    2,
    3,
    4
]

The diff would look like

 a = [
     1,
     2,
-    3
+    3,
+    4
 ]

Whereas if you had started with a trailing comma, like

a = [
    1,
    2,
    3,
]

Then the diff would just be

 a = [
     1,
     2,
     3,
+    4,
 ]