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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 fitting_rmsd(w_fit, C_fit, r_fit, Xs):
    '''Calculate the RMSD of fitting.'''
    return np.sqrt(sum((geometry.point_line_distance(p, C_fit, w_fit) - r_fit) ** 2
                    for p in Xs) / len(Xs))