Initialization of bitarray

I have the following storage in Python (20 x 1):

storage = 0b11111111111111111111

How to make this more dynamic? How to initialize it with e.g. 30 oder 40 bits without typing 1 forty times, that is.

>Solution :

You can use the bit shift operator, like this:

storage = (1 << 40) - 1

Replace 40 with the number of bits.

EDIT: As mentioned in @slothrop’s comment, there’s also another solution:

storage = 2**40 - 1