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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 ConvBPDNOptionsDefaults(method='admm'):
 """Get defaults dict for the ConvBPDN class specified by the ``method`` parameter. """


    dflt = copy.deepcopy(cbpdn_class_label_lookup(method).Options.defaults)
    if method == 'admm':
        dflt.update({'MaxMainIter': 1, 'AutoRho':
                     {'Period': 10, 'AutoScaling': False,
                      'RsdlRatio': 10.0, 'Scaling': 2.0,
                      'RsdlTarget': 1.0}})
    else:
        dflt.update({'MaxMainIter': 1, 'BackTrack':
                     {'gamma_u': 1.2, 'MaxIter': 50}})
    return dflt