A tuple is like a list, except that it is immutable -
its contents can't be changed once created.
Tuples are defined in parentheses, rather than square brackets,
or just as a series of comma-separated values with nothing around them.
>>> x = (1, 2, 3)
A major use for tuples is for multiple return values from a function.
>>> def doubledouble(x,y): ... return x*2, y*2 ... >>> a,b = doubledouble(3,5) >>> print a 6 >>> print b 10