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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 _tilt(omega, b, psi):
 """ Compute the tilt of the PG density for value omega and tilt psi. :param omega: point at which to evaluate the density :param psi: tilt parameter """

    return np.cosh(psi/2.0)**b * np.exp(-psi**2/2.0 * omega)