value equality vs. object equality, aliasing, list is mutable DEMO

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#quote from MIT 'introduction to computation and programming using python, Revised'
Techs = ['MIT', 'CalTech']Ivys = ['Harvard', 'Yale', 'Brown']univ = [Techs, Ivys]univ1 = [['MIT', 'CalTech'], ['Harvard', 'Yale', 'Brown']]print univ[['MIT', 'CalTech'], ['Harvard', 'Yale', 'Brown']]print univ1[['MIT', 'CalTech'], ['Harvard', 'Yale', 'Brown']]print univ == univ1Trueprint id(univ), id(univ1)121487688 122964408print id(univ) == id(univ1)FalseTechs.append('xxx')print univ[['MIT', 'CalTech', 'xxx'], ['Harvard', 'Yale', 'Brown']]print univ1[['MIT', 'CalTech'], ['Harvard', 'Yale', 'Brown']]Ivys[0] = 'kkk'print univ[['MIT', 'CalTech', 'xxx'], ['kkk', 'Yale', 'Brown']]print univ1[['MIT', 'CalTech'], ['Harvard', 'Yale', 'Brown']]

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