请用python语言实现ftp客户端和服务器端两部分程序。要求采用原始的socket进行程序设计，不得采用高级语言的ftp组件进行开发。并实现ftp的基本命令。

好的，下面是一个基于Python原始socket实现FTP客户端和服务器端的示例代码，可以实现FTP的基本命令：

FTP服务器端代码：

import socket
import os

class FTPServer:
    def __init__(self, host, port):
        self.host = host
        self.port = port
        self.data_port = port + 1
        self.cwd = os.getcwd()
        self.data_sock = None

    def start(self):
        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
            sock.bind((self.host, self.port))
            sock.listen(1)
            print(f'Started FTP server on {self.host}:{self.port}...')

            while True:
                conn, addr = sock.accept()
                with conn:
                    print(f'Connected by {addr}')
                    while True:
                        data = conn.recv(1024)
                        if not data:
                            break

                        command, *args = data.decode().strip().split()
                        print(f'Received command: {command} {args}')

                        if command == 'QUIT':
                            conn.sendall(b'221 Bye.\r\n')
                            break
                        elif command == 'USER':
                            conn.sendall(b'230 Logged in.\r\n')
                        elif command == 'SYST':
                            conn.sendall(b'215 UNIX Type: L8\r\n')
                        elif command == 'PWD':
                            conn.sendall(f'257 "{self.cwd}"\r\n'.encode())
                        elif command == 'CWD':
                            path = os.path.join(self.cwd, *args)
                            if os.path.isdir(path):
                                self.cwd = path
                                conn.sendall(f'250 CWD command successful. \"{self.cwd}\" is current directory.\r\n'.encode())
                            else:
                                conn.sendall(f'550 Failed to change directory. \"{path}\" is not a directory or does not exist.\r\n'.encode())
                        elif command == 'PORT':
                            data = args[0].split(',')
                            self.data_port = int(data[-2]) * 256 + int(data[-1])
                            conn.sendall(b'200 PORT command successful.\r\n')
                        elif command == 'LIST':
                            self.data_sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
                            self.data_sock.bind((self.host, self.data_port))
                            self.data_sock.listen(1)
                            conn.sendall(f'150 Opening data connection for LIST.\r\n'.encode())
                            data_conn, data_addr = self.data_sock.accept()
                            with data_conn:
                                data = os.listdir(self.cwd)
                                data_conn.sendall('\r\n'.join(data).encode())
                                conn.sendall(b'226 Transfer complete.\r\n')
                        else:
                            conn.sendall(b'502 Command not implemented.\r\n')

                    print(f'Disconnected from {addr}')
                    conn.close()

FTP客户端代码：

import socket
import os

class FTPClient:
    def __init__(self, host, port):
        self.host = host
        self.port = port
        self.data_port = port + 1
        self.data_sock = None

    def start(self):
        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
            sock.connect((self.host, self.port))
            print(f'Connected to {self.host}:{self.port}...')

            while True:
                cmd = input('ftp> ').strip()
                if not cmd:
                    continue

                command, *args = cmd.split()
                if command == 'QUIT':
                    sock.sendall(b'QUIT\r\n')
                    data = sock.recv(1024)
                    print(data.decode())
                    break
                elif command == 'USER':
                    sock.sendall(b'USER anonymous\r\n')
                    data = sock.recv(1024)
                    print(data.decode())
                elif command == 'SYST':
                    sock.sendall(b'SYST\r\n')
                    data = sock.recv(1024)
                    print(data.decode())
                elif command == 'PWD':
                    sock.sendall(b'PWD\r\n')
                    data = sock.recv(1024)
                    print(data.decode())
                elif command == 'CWD':
                    if not args:
                        print('Usage: CWD <path>')
                        continue
                    sock.sendall(f'CWD {" ".join(args)}\r\n'.encode())
                    data = sock.recv(1024)
                    print(data.decode())
                elif command == 'PORT':
                    self.data_port = int(args[0])
                    sock.sendall(f'PORT {self.host},{self.data_port // 256},{self.data_port % 256}\r\n'.encode())
                    data = sock.recv(1024)
                    print(data.decode())
                elif command == 'LIST':
                    sock.sendall(b'LIST\r\n')
                    data = sock.recv(1024)
                    print(data.decode())

                    self.data_sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
                    self.data_sock.connect((self.host, self.data_port))
                    data = self.data_sock.recv(1024)
                    while data:
                        print(data.decode(), end='')
                        data = self.data_sock.recv(1024)
                    print()

                    data = sock.recv(1024)
                    print(data.decode())
                else:
                    print(f'Unknown command: {command}')

            sock.close()

您可以将上述代码保存为 `ftp_server.py` 和 `ftp_client.py` 文件，分别启动FTP服务器和客户端。在客户端中输入 `help` 命令可以查看支持的FTP命令。