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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 __profile_definition(self, pipeline_name):
 """ Prepare the profiles extraction from a specific profile """

        pipe = self.flsh.Operations[pipeline_name]
        x_st = pipe.GetUserVariable(PROFILE_LENGTH_ST).Variable()
        x_non_st = pipe.GetUserVariable(PROFILE_LENGTH_NON_ST).Variable()
        timesteps = pipe.GetUserVariable(PROFILE_TIME).Variable()
        self.pipes[pipeline_name] = {'grid': x_st,
                                     'non_st_grid': x_non_st,
                                     'timesteps': timesteps,
                                     'data': {}
                                    }
        return pipe