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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 isclose(a, b, atol):
 """ A replacement for np.isclose that does fewer checks and validation and as a result is roughly 4x faster. Note that this is used in tight loops, and as such a and b MUST be np.ndarray, not list or "array-like" Parameters a : np.ndarray To be compared b : np.ndarray To be compared atol : float Acceptable distance between `a` and `b` to be "close" Returns close : np.ndarray, bool Per- element closeness """

    diff = a - b
    close = np.logical_and(diff > -atol, diff < atol)
    return close