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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 hessian(self, coordinates):
 """Compute the force-field Hessian for the given coordinates. Argument: | ``coordinates`` -- A numpy array with the Cartesian atom coordinates, with shape (N,3). Returns: | ``hessian`` -- A numpy array with the Hessian, with shape (3*N, 3*N). """

        # N3 is 3 times the number of atoms.
        N3 = coordinates.size
        # Start with a zero hessian.
        hessian = numpy.zeros((N3,N3), float)
        # Add the contribution of each term.
        for term in self.terms:
            term.add_to_hessian(coordinates, hessian)
        return hessian