It’s a bitmask. In low-level computation, it’s an efficient way to clear out bits of register. In this case, the mask has all bits of a 32 bit integer set, except the signed bit. The signed bit is the bit that determines if the number is positive or negative. ANDing (`&`

) with this mask effectively sets the signed bit to 0, which means the number will always be positive.

`a && b`

is `True`

when both `a`

and `b`

are `True`

.`a & b`

is `1`

when both `a`

and `b`

are `1`

, for each binary digit in a and b.

Python has support for binary literals, with the `0b`

prefix. Here are some 3-bit numbers being `and`

ed together.

```
>>> 0b101 & 0b110 == 0b100
True
>>> 0b011 & 0b111 == 0b011
True
>>> 0b011 & 0b110 == 0b010
True
```