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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 send_file(self, filename, mimetype=None, restricted=True, checksum=None, trusted=False, chunk_size=None, as_attachment=False):
 """Send the file to the client."""

        try:
            fp = self.open(mode='rb')
        except Exception as e:
            raise StorageError('Could not send file: {}'.format(e))

        try:
            md5_checksum = None
            if checksum:
                algo, value = checksum.split(':')
                if algo == 'md5':
                    md5_checksum = value

            # Send stream is responsible for closing the file.
            return send_stream(
                fp,
                filename,
                self._size,
                self._modified,
                mimetype=mimetype,
                restricted=restricted,
                etag=checksum,
                content_md5=md5_checksum,
                chunk_size=chunk_size,
                trusted=trusted,
                as_attachment=as_attachment,
            )
        except Exception as e:
            fp.close()
            raise StorageError('Could not send file: {}'.format(e))