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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 ccmod_class_label_lookup(label):
 """Get a CCMOD class from a label string."""


    clsmod = {'ism': admm_ccmod.ConvCnstrMOD_IterSM,
              'cg': admm_ccmod.ConvCnstrMOD_CG,
              'cns': admm_ccmod.ConvCnstrMOD_Consensus,
              'fista': fista_ccmod.ConvCnstrMOD}
    if label in clsmod:
        return clsmod[label]
    else:
        raise ValueError('Unknown ConvCnstrMOD solver method %s' % label)