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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 _density_par(self,dangle,tdisrupt=None,approx=True, higherorder=None):
 """The raw density as a function of parallel angle, approx= use faster method that directly integrates the spline representation"""

        if higherorder is None: higherorder= self._higherorderTrack
        if tdisrupt is None: tdisrupt= self._tdisrupt
        if approx:
            return self._density_par_approx(dangle,tdisrupt,
                                            higherorder=higherorder)
        else:
            return integrate.quad(lambda T: numpy.sqrt(self._sortedSigOEig[2])\
                                      *(1+T*T)/(1-T*T)**2.\
                                      *self.pOparapar(T/(1-T*T)\
                                                          *numpy.sqrt(self._sortedSigOEig[2])\
                                                          +self._meandO,dangle),
                                  -1.,1.)[0]