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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _checker_mixer(slice1, slice2, checker_size=None):
 """Mixes the two slices in alternating areas specified by checkers"""


    checkers = _get_checkers(slice1.shape, checker_size)
    if slice1.shape != slice2.shape or slice2.shape != checkers.shape:
        raise ValueError('size mismatch between cropped slices and checkers!!!')

    mixed = slice1.copy()
    mixed[checkers > 0] = slice2[checkers > 0]

    return mixed