# suppose the list is x:

return [x[i:i+2] for i in range(0, len(x), 2)]

# or, as a generator

return x[i:i+2]for i in range(0,len(x),2)

a,b=5,6

print(a,b)  

a=a+b  

b=a-b   

a=a-b

print(a,b)

a = 1

b = 2

# Swap a and b

a, b = b, a

in python below is how you swap 2 elements of list

            x[i+1],x[i]=x[i],x[i+1]

Don't use function swap(user defined or pre-defined)

def swapPositions(list, pos1, pos2):

    list[pos1], list[pos2]=list[pos2], list[1]

    return list

List=[1,3,5,7,9,11]

pos1, pos2=1,3

print(swapPositions(list, pos1-1, pos2-1))