https://www.instagram.com/accounts/login/ajax/

POST /accounts/login/ajax/ HTTP/1.1
Host: www.instagram.com
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:49.0) Gecko/20100101 Firefox/49.0
Accept: */*
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate, br
X-CSRFToken: 3mUsLSQaAFhlGpQp29ofI8o9MMx9xUaN
X-Instagram-AJAX: 1
Content-Type: application/x-www-form-urlencoded
X-Requested-With: XMLHttpRequest
Referer: https://www.instagram.com/?hl=en
Content-Length: 42
Cookie: csrftoken=3mUsLSQaAFhlGpQp29ofI8o9MMx9xUaN; mid=WFXjggAEAAHqqA9DSs19tM4Ul97a; ig_pr=1; ig_vw=1366
Connection: keep-alive
username=dssdsdsds&password=fsdfdfsfdsfsfs