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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 upgradedb(options):
 """ Add 'fake' data migrations for existing tables from legacy GeoNode versions """

    version = options.get('version')
    if version in ['1.1', '1.2']:
        sh("python manage.py migrate maps 0001 --fake")
        sh("python manage.py migrate avatar 0001 --fake")
    elif version is None:
        print "Please specify your GeoNode version"
    else:
        print "Upgrades from version %s are not yet supported." % version