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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 __read_line(self):
 """Read one line from the server. An internal buffer is used to read data from the server (blocks of Client.read_size bytes). If the buffer is not empty, we try to find an entire line to return. If we failed, we try to read new content from the server for Client.read_timeout seconds. If no data can be retrieved, it is considered as a fatal error and an 'Error' exception is raised. :rtype: string :return: the read line """

        ret = b""
        while True:
            try:
                pos = self.__read_buffer.index(CRLF)
                ret = self.__read_buffer[:pos]
                self.__read_buffer = self.__read_buffer[pos + len(CRLF):]
                break
            except ValueError:
                pass
            try:
                nval = self.sock.recv(self.read_size)
                self.__dprint(nval)
                if not len(nval):
                    break
                self.__read_buffer += nval
            except (socket.timeout, ssl.SSLError):
                raise Error("Failed to read data from the server")

        if len(ret):
            m = self.__size_expr.match(ret)
            if m:
                raise Literal(int(m.group(1)))

            m = self.__respcode_expr.match(ret)
            if m:
                if m.group(1) == b"BYE":
                    raise Error("Connection closed by server")
                if m.group(1) == b"NO":
                    self.__parse_error(m.group(2))
                raise Response(m.group(1), m.group(2))
        return ret