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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 get_coordinate_system(self):
 """ Check self.Data for available coordinate systems. Returns --------- initial_coordinate, coordinate_list : str, list i.e., 'geographic', ['specimen', 'geographic'] """

        coordinate_list = ['specimen']
        initial_coordinate = 'specimen'
        for specimen in self.specimens:
            if 'geographic' not in coordinate_list and self.Data[specimen]['zijdblock_geo']:
                coordinate_list.append('geographic')
                initial_coordinate = 'geographic'
            if 'tilt-corrected' not in coordinate_list and self.Data[specimen]['zijdblock_tilt']:
                coordinate_list.append('tilt-corrected')
        return initial_coordinate, coordinate_list