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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 CreateConfigHBuilder(env):
 """Called if necessary just before the building targets phase begins."""

    action = SCons.Action.Action(_createConfigH,
                                 _stringConfigH)
    sconfigHBld = SCons.Builder.Builder(action=action)
    env.Append( BUILDERS={'SConfigHBuilder':sconfigHBld} )
    for k in list(_ac_config_hs.keys()):
        env.SConfigHBuilder(k, env.Value(_ac_config_hs[k]))