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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 _vmomentsurfaceIntegrand(vR,vT,R,az,df,n,m,sigmaR1,sigmaT1,t,initvmoment):
 """Internal function that is the integrand for the velocity moment times surface mass integration"""

    o= Orbit([R,vR*sigmaR1,vT*sigmaT1,az])
    return vR**n*vT**m*df(o,t)/initvmoment