文档服务新年特惠

import os
from datetime import datetime

class DocumentService:
    def __init__(self, base_url):
        self.base_url = base_url
    
    def upload_document(self, file_path):
        # 模拟上传文档
        if os.path.exists(file_path):
            print(f"Document {file_path} uploaded successfully.")
        else:
            print("File not found.")
    
    def get_document(self, doc_id):
        # 模拟获取文档
        print(f"Fetching document with ID {doc_id}...")
        return f"Content of document {doc_id}"
    
    def apply_promotion(self, promotion_code):
        # 模拟应用优惠码
        if promotion_code == "NEWYEAR2023":
            print("Promotion applied successfully! Enjoy your discount.")
        else:
            print("Invalid promotion code.")

# 示例使用
doc_service = DocumentService("https://example.com/docs")
doc_service.upload_document("sample.txt")
print(doc_service.get_document("12345"))
doc_service.apply_promotion("NEWYEAR2023")