Implement Bit Manipulation TricksStep 2 of 5

Detect Powers of Two

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Step 2: Detect Powers of Two

A positive power of two has exactly one bit set: 1, 2, 4, 8, 16, and so on.

That single-bit property gives a beautiful test. If n is a power of two, then n - 1 flips that one bit off and turns every lower bit on, so n & (n - 1) is 0. Watch out for 0 and negatives, which are not powers of two.

Implement is_power_of_two(n) to return True when n is a positive power of two, else False.

Hints
Starter code
def count_set_bits(n):
    count = 0
    while n:
        n &= n - 1
        count += 1
    return count


def is_power_of_two(n):
    """Return True if n is a positive power of two, else False.

    A power of two has exactly one set bit, so n & (n - 1) == 0.
    """
    # TODO: return True only when n is positive AND (n & (n - 1)) == 0.
    pass
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