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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 _deleteComboBoxes(self, row):
 """ Deletes all comboboxes of a row """

        tree = self.tree
        model = self.tree.model()

        for col in range(self.COL_FIRST_COMBO, self.maxCombos):
            logger.debug("Removing combobox at: ({}, {})".format(row, col))
            tree.setIndexWidget(model.index(row, col), None)

        self._comboBoxes = []