Parsing string with multiple HTTP requests

Could you please clarify what the behaviour is when execute() gets passed a string with two (or even more) HTTP requests directly behind each other (seperated by "\r\n\r\n").
In my example

```
pars.get_headers()["HOST"]
```

returned the Host field of **both** requests seperated with a comma (although the hosts were the same).

Interestingly

```
pars.get_url()
```

returned just the URL of the **second** request.

先通过 execute() 重现示例，然后检查 get_headers() 和 get_url() 如何处理包含多个 HTTP 请求、且请求之间由 "\r\n\r\n" 分隔的字符串。确定并记录对多个请求的预期行为，包括是否应解析两个请求，以及返回的请求头和 URL 应如何表示。

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