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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 prev(self, n=1):
 """Get the previous n data from file. Keyword argument: n -- number of structs to be retrieved (default 1) Must be greater than 0. Return: A data in the format of obj_fmt, if n = 1. A list of structs, otherwise. """

        # Current position - #data
        i = abs(self.tell - n)

        # Get the next n data starting from i
        return self.get(i, n)