python-requests does not grab JSESSIONID

I'm trying to scrape a website using requests. However, a post method that I need to use requires the headers below. I can fill everything apart from the JSESSION ID. The only way I can get this post method to work is if I manually go into the browser, start a session and inspect the page to retrieve the JSESSIONID.

I am looking for a way to retrieve this JSESSIONID using the requests package in python. I saw some suggestions for using a session. However, the requests session does not grab the JSESSIONID, which is the only thing I need. How should I go about a possible solution?

link to the website here

Host: 
Connection: 
Content-Length:
Accept: 
X-Requested-With: 
User-Agent: 
Content-Type:
Sec-GPC: 
Origin: 
Sec-Fetch-Site: 
Sec-Fetch-Mode: 
Sec-Fetch-Dest: 
Referer: 
Accept-Encoding:
Accept-Language: 
Cookie: _1aa19=; JSESSIONID=;

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