[BUG]网易云长歌单列表不全

**问题描述（Question description）**
使用 `music-dl --playlist` 下载发现获取到的列表不全。通过网页查看列表发现可能是网易做了限制，因为web显示“查看更多内容，请下载客户端”

- 搜索的关键字（Keyword）：`music-dl --playlist`
- 出错的音乐源（Music source）：网易云
- 使用的命令（Command used）：`music-dl --playlist`

**使用的环境（Environment）**
- 安装方式（Installation method）：pip3 install
- music-dl版本（music-dl version）：3.0.1
- 操作系统版本（OS version）：macOS 10.15
- Python版本（Python version）：3.7.5

The issue is about incomplete playlist fetching from NetEase Cloud Music. Start by examining the web scraping logic in the NetEase source module (likely in a file like `netsource.py` or similar). Check for pagination or client-side restrictions. Simulate the web request to see the 'download client' message. Understand how the playlist API is called and where the truncation happens. A fix may involve modifying request headers or parsing a different endpoint.

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