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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 delete_one_letter(self, letter=RIGHT):
 """Delete one letter the right or the the left of the cursor."""


        assert letter in (self.RIGHT, self.LEFT)

        if letter == self.LEFT:
            papy = self.cursor
            self.text = self.text[:self.cursor - 1] + self.text[self.cursor:]
            self.cursor = papy - 1

        else:
            self.text = self.text[:self.cursor] + self.text[self.cursor + 1:]