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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 write(self, fptr):
 """Write a NumberList box to file. """

        fptr.write(struct.pack('>I4s',
                               len(self.associations) * 4 + 8, b'nlst'))

        fmt = '>' + 'I' * len(self.associations)
        write_buffer = struct.pack(fmt, *self.associations)
        fptr.write(write_buffer)