python - Checking if List contains all items from another list

Question

What is the easiest/fastest way to check if a list of tuples contains all the the tuples that another list does. For example:

t1 = [ (1,2), (3,4), (5,6), (7,8), (9,10), (11,12) ]
t2 = [ (3,4), (11,12) ]

would be a true case since t1 contains all the tuples in t2. I tried something like:

[i for e in t2 for i in t1 if e in i]
sorted(t1) == sorted(t2)

but this seemed to always return true. Is there a better way?

Answer 1

You can use sets

t1 = [ (1,2), (3,4), (5,6), (7,8), (9,10), (11,12) ]
t2 = [ (3,4), (11,12) ]
set(t2).issubset(t1)
# returns true

# or equivalent use '<=' so
set(t2) <= set(t1)
# returns true