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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 clean_values(self):
 """Cleans the values in each cell. Calls either the user provided clean_value, or the class defined clean value. """

    for row in self.rows:
      for index, cell in enumerate(row):
        self.set_cell_value(row, index, self.clean_value(self.get_cell_value(cell)))
    return self