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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 export(self, filename, offset=0, length=None):
 """Exports byte array to specified destination Args: filename (str):
 destination to output file offset (int):
 byte offset (default: 0) """

        self.__validate_offset(filename=filename, offset=offset, length=length)

        with open(filename, 'w') as f:
            if length is None:
                length = len(self.data) - offset

            if offset > 0:
                output = self.data[offset:length]
            else:
                output = self.data[:length]

            f.write(output)