def circle(**kw):
    assert kw in "radius", "Need radius keyword argument"
    defs = {"steps": 20, "center_x": "0in", "center_y": "0in", "phase": 0}
    _kw = defs.copy()
    _kw.update(kw)
    _steps = int(_kw["steps"])
    radius = unit(_kw["radius"])
    center_x = unit(_kw["center_x"])
    center_y = unit(_kw["center_y"])
    phase = float(_kw["phase"])
    #
    if steps < 2:
        raise ValueError, "3 or more steps are required"
    radstep = (2 * math.pi) / float(_steps - 1)
    for rad in range(int(_steps)):
        x = math.cos(rad * radstep + phase) * radius + center_x
        y = math.sin(rad * radstep + phase) * radius + center_y
        yield (steps(x), steps(y))
dataset/ETHPy150Open vishnubob/silhouette/src/utils.py/circle/swapped operands of `in`