Dataframe transform column for each day into rows

Question

I have a csv that is formatted similar to the following:

Attr1	Attr2	10/1/22	10/2/22	10/3/22	etc.
Red	Square	5	10	12	0
Blue	Square	11	8	2	1
Red	Circle	1	12	3	4
Blue	Circle	3	5	7	6

I can load this into a dataframe, but I want to get it into this format:

Attr1	Attr2	Date	Qty
Red	Square	10/1/22	5
Red	Square	10/2/22	10
Red	Square	10/3/22	12
etc.	.	.	.
etc.	.	.	.
Blue	Circle	10/1/22	3
Blue	Circle	10/2/22	5
Blue	Circle	10/3/22	7

Issues:

1. the number of columns is variable (one per day) increasing each day
2. want to "explode" the date columns into 1 row per day while keeping the "attribute" columns

This is reformatting issue. No need for any aggregation or calculaiton.

Any ideas how to proceed? Thank you.