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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 exponential(x, y, xscale, yscale):
 """ Two-dimensional oriented exponential decay pattern. """

    if xscale==0.0 or yscale==0.0:
        return x*0.0

    with float_error_ignore():
        x_w = np.divide(x,xscale)
        y_h = np.divide(y,yscale)
        return np.exp(-np.sqrt(x_w*x_w+y_h*y_h))