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Introduction to Bitwise Operators
The Man Behind the Bit Mask

A bit mask is just a variable that aids you with bitwise operations. A bit mask can help you turn specific bits on, turn others off, or just collect data from an integer about which bits are on or off.

``````num  = 0b1100
if desired > 0:
print "Bit was on"``````

In the example above, we want to see if the third bit from the right is on.

1. First, we first create a variable `num` containing the number 12, or `0b1100`.
2. Next, we create a `mask` with the third bit on.
3. Then, we use a bitwise-and operation to see if the third bit from the right of `num` is on.
4. If `desired` is greater than zero, then the third bit of `num` must have been one.

### Instructions

1.

Define a function, `check_bit4`, with one argument, `input`, an integer.

It should check to see if the fourth bit from the right is on.

If the bit is on, `return "on"` (not `print`!)

If the bit is off, `return "off"`.

Check the Hint for some examples!