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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 expected_part_size(self, part_number):
 """Get expected part size for a particular part number."""

        last_part = self.multipart.last_part_number

        if part_number == last_part:
            return self.multipart.last_part_size
        elif part_number >= 0 and part_number < last_part:
            return self.multipart.chunk_size
        else:
            raise MultipartInvalidPartNumber()