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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 generate(env):
 """ Add builders and construction variables for the DistTar builder. """


    disttar_action=SCons.Action.Action(disttar, disttar_string)
    env['BUILDERS']['DistTar'] =  Builder(
            action=disttar_action
            , emitter=disttar_emitter
            , suffix = disttar_suffix
            , target_factory = env.fs.Entry
    )

    env.AppendUnique(
        DISTTAR_FORMAT = 'gz'
    )