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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 seek(self, pos):
 """ Move to new input file position. If position is negative or out of file, raise Exception. """

        if (pos > self.file_size) or (pos < 0):
            raise Exception("Unable to seek - position out of file!")
        self.file.seek(pos)