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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 _get_fname_len(self, bufflen=128):
 """Returns the number of bytes designated for the filename."""

        buff = self.meta.peek(bufflen)
        strlen = buff.find('\0')
        for i, b in enumerate(buff[strlen:]):
            if b != '\0':
                return strlen+i
        return bufflen