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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 _2ndDerivInt(x,y,z,dens,densDeriv,b2,c2,i,j,glx=None,glw=None):
 """Integral that gives the 2nd derivative of the potential in x,y,z"""

    def integrand(s):
        t= 1/s**2.-1.
        m= numpy.sqrt(x**2./(1.+t)+y**2./(b2+t)+z**2./(c2+t))
        return (densDeriv(m)
                *(x/(1.+t)*(i==0)+y/(b2+t)*(i==1)+z/(c2+t)*(i==2))
                *(x/(1.+t)*(j==0)+y/(b2+t)*(j==1)+z/(c2+t)*(j==2))/m\
                    +dens(m)*(i==j)*((1./(1.+t)*(i==0)+1./(b2+t)*(i==1)+1./(c2+t)*(i==2))))\
                    /numpy.sqrt((1.+(b2-1.)*s**2.)*(1.+(c2-1.)*s**2.))
    if glx is None:
        return integrate.quad(integrand,0.,1.)[0]
    else:
        return numpy.sum(glw*integrand(glx))