def METHOD_NAME(self,R=0.4):
    if   R == 0.3: return self.physObj.pfIsolationR03().sumChargedParticlePt 
    elif R == 0.4: return self.physObj.pfIsolationR04().sumChargedParticlePt 
    raise RuntimeError("Muon chargedAllIso missing for R=%s" % R)