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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, chunk):
 """WSGI callable to write unbuffered data to the client. This method is also used internally by start_response (to write data from the iterable returned by the WSGI application). """

        if not self.started_response:
            raise AssertionError('WSGI write called before start_response.')

        chunklen = len(chunk)
        rbo = self.remaining_bytes_out
        if rbo is not None and chunklen > rbo:
            if not self.req.sent_headers:
                # Whew. We can send a 500 to the client.
                self.req.simple_response(
                    '500 Internal Server Error',
                    'The requested resource returned more bytes than the '
                    'declared Content-Length.',
                )
            else:
                # Dang. We have probably already sent data. Truncate the chunk
                # to fit (so the client doesn't hang) and raise an error later.
                chunk = chunk[:rbo]

        self.req.ensure_headers_sent()

        self.req.write(chunk)

        if rbo is not None:
            rbo -= chunklen
            if rbo < 0:
                raise ValueError(
                    'Response body exceeds the declared Content-Length.',
                )