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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 mex_hat_dir(x, y, sigma):
 r"""Directional Mexican hat This method implements a directional Mexican hat (or Ricker) wavelet. Parameters x : float Input data point for Gaussian y : float Input data point for Mexican hat sigma : float Standard deviation (filter scale) Returns ------- float directional Mexican hat filtered data point Examples -------- 0.17606952612856686 """


    x = check_float(x)
    sigma = check_float(sigma)

    return -0.5 * (x / sigma) ** 2 * mex_hat(y, sigma)