def _sqrt_nearest(n, a):
    """Closest integer to the square root of the positive integer n.  a is
    an initial approximation to the square root.  Any positive integer
    will do for a, but the closer a is to the square root of n the
    faster convergence will be.

    """
    if n <= 0 or a <= 0:
        raise ValueError("Both arguments to _sqrt_nearest should be positive.")

    b=0
    while a != b:
        b, a = a, -n//a-a>>1
    return a
dataset/ETHPy150Open azoft-dev-team/imagrium/env/Lib/decimal.py/_sqrt_nearest/swapped operands of `-`